Super Subs Inc. is planning on hiring new employees for the summer. They want to make sure their new employees are available to work on the busiest day of the week. Below is a chart of their four different stores, and how many sub sandwiches they sold at each store the previous week. According to this chart, which day will the new hires most likely need to work?

1. Wednesday

2. Thursday

3. Friday

4. Saturday

5. Sunday

Super Subs Inc. may need to shut down a store due to the bad economy. According to the chart, which store would they most likely shut down?

1. Store A

2. Store B

3. Store C

4. Store D

5. None of the Stores

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com

What Percent OF the Original amount IS the Difference between the two amounts?

P × O = D

Percent decrease is pretty much the same thing. What percent of the original amount is the difference between the two amounts? Only difference in figuring it out is that the second amount is lower than the first, not higer. No sweat. The percent times the original amount still equals the difference. It’s just a decrease, not an increase. Get it?

Let’s look at it. Here’s a practice problem.

I filled up my car, so it had 15 gallons of gas in the tank. So, I drove out to my uncle’s house and back, and it took $18 in gas at $2 per gallon to fill up the tank. What was the percentage decrease in gas during the trip?

Did I get you with a tough one? More than jus’ one step here. Try to figure it out, then I’ll walk you through it…

Okay, here’s the deal. You need to do some steps to get the info you need to solve the problem… so what info do you need? Well, here’ s the formula we said….

P × O = D

Percent decrease (P) is what you’re tryin’ to find. Original value, you know that, it was 15 gallons, like the problem said.

P × 15 = D

But what’s the difference between the old amount of gas an’ the new one? Well, you gotta figure it out. It’s the amount of gas that got used, right? The info you have is that it took $18 at $2 per gallon to fill up the tank. How much gas can you get at $2 a gallon for 18 bucks? You know that, right? Divide 18 by 2, an’ you got 9 gallons. It took 9 gallons to fill up the tank, so the gas left at the end of the trip was 6 gallons. The difference between the 15 gallons started with an’ the 6 gallons ended with is 9 gallons. Get it?

P × 15 = 9

So, the percentage decrease is 9 divided by 15, or .6

P = 9 ÷ 15 = .6

Now, you gotta turn .6 into a percentage, an’ you jus’ move the decimal point over two to the right. So’s it’s 60%.

P = 9 ÷ 15 = .6 = 60%

The guy used 60% of his gas on the trip.

Knowin’ what a percent increase or decrease problem is askin’ is the big thing, and bein’ able to think through word problems. Let me know if you got any GED math that’s givin’ you a problem, an’ I’ll help you out.

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.

I got a new hard drive, to back up my computer. The old hard drive I was usin’ was 250 GB. Now, the new one’s 640 GB. Sweet! So, what’s the percent increase in hard drive space from the old hard drive to the new one?

Give it a minute, try to work it out. What’dya think?

Here’s how I’d work through this one. First, you got to know what they mean when they say “what’s the percent increase?” It means, what PERCENT of the ORIGINAL AMOUNT is the DIFFERENCE BETWEEN (increase between) the two amounts. That’s puttin’ it in some context, right? First off, you got 3 important numbers. (1) PERCENT (P) = what you’re trying to find. (2) ORIGINAL (O) AMOUNT. (3) DIFFERENCE (D) BETWEEN old and new amounts.

Now, in math, “of” usually means “times.” And “is” usually means “equals.” So, I could put it like this.

P × O = D

What Percent OF the Original amount IS the Difference between the two amounts?

Well, you know the original amount. Dat’s my original hard drive size, 250 GB.

P × 250 = D

And to find the “difference” between two things, you gotta subtract. So the difference is the two amounts subtracted: 640 − 250 = 390

P × 250 = 390

To find P, the percent, you got to get P all by itself. So, to get rid of the “times 250,” you divide both sides by 250…

P × 250 ÷ 250 = 390 ÷ 250

P × 1 = 390 ÷ 250

P = 390 ÷ 250

P = 1.56

Now, P’s supposed to be a percent. To change a number to a percent, move the decimal place two to the right… the answer is:

156%

Let’s check it out… 100% bigger would mean it’s 250 GB bigger… one whole hard drive bigger. And it’s more than that. It’s more like 1-1/2 times bigger… that’s 150%. So the answer makes sense, right? Now, can you do the same thing with a percent decrease problem? What if it asked what the percent decrease was from 640 GB to 250 GB? Think about it, I’ll have a percent decrease problem in my next post….

Get that GED quick… you can do it!

For more information about the GED test and GED test preparation, visit The GED Academy at http://www.passGED.com.

Plus, remember ’bout Stephen Wolfram? Yup, mathematics guy, wrote some software to do advanced math real quick. Well, he’s starting a new online website, and here’s what it does… You type in your question, and it’s got a big encyclopedia of a bunch of info, right? So it figures out your question… and sends you the answer. Don’t think that math ain’t at the bottom of it. The website’s up later this month… called Wolfram Alpha. so check it out, the next cool thing, brought to y’all by MATH.

Math ain’t too hard. Jus’ take it step by step, once you get the basics down, you get there. How ’bout a practice question to get the juices goin’? Here it is…

Annie is an interior designer, and she’s got a budget of $345 to buy fabric for drapes. She needs 12 yards of fabric. The fabric that she really wants, Fabric A, costs $29 per yard. Her second choice, Fabric B, costs $27.50 per yard, and her third choice, Fabric C, costs $26 per yard. She wants to buy her top choice that she can afford and stay in budget. Which fabric should she buy?

1) Fabric A

2) Fabric B

3) Fabric C

4) All the fabrics are too expensive.

So… what’d'ya get? And how’d ya go about it? Here’s what I figure… I could multiply the cost of each fabric by 12 yards to find out how much each would cost, but that seems like too much work to me. So I wanna take the shortest short-cut I got. Here’s what I did… take the total budget, $345, and divide it by 12 yards of fabric. That gonna give me the budget PER YARD, then I can jus’ compare that with all the prices.  $345 divided by 12 is $28.75, so I got my max price per yard. Now, I can’t afford the $29 fabric, jus barely. Don’t know bout you, but I’d be all smooth-talkin’ the fabric store owner to try to get a discount. But dat ain’ t part of the question. So the answer’s 2, Answer B, the $27.50 fabric.

And, you notice, this GED question’s all ’bout a real-life job that’d really use this kinda math. So, keep it in mind… math’s real good for your future!

Two cyclists start biking from a trail’s start 3 hours apart. The second cyclist travels at 10 miles per hur ans start 3 hours after the first cyclist who is traveing at 6 miles per hour. How much time will pass before the second cyclist catches up with the first from the time the second cyclist started biking

Okay. bicyclists. start 3 hours apart. You want to know when they meet, so you want to know when the distance is the same.

distance = rate × time

So, bicyclist 1, let’s call him “A” … “A” = 6 mph × time
An’ bicyclist 2, let’s call him “B” … “B” = 10 mph × (time – 3)

The minus 3 is cuz he’s travelin’ 3 hours less than the other one. Now, because “A” = “B” (they’ve gone the same distance when they meet), you’ve got an equation your can solve:

6 × time = 10 × (time – 3) …
that’s the same as: 6t = 10(t – 3)

Now, it’s jus’ algebra, right? you multiply the 10 by both the “t” and the 3…

6t = 10t – 30

Now, subtract 10t from both sides to get the “t”s all together… remember, cuz it’s minus 30, your 30’s gonna be negative:

6t – 10t = -30
-4t = -30

Now, divide by -4 to get t all by itself… a negative divided by a negative is a positive, which is good, otherwise they’d be time travelin’ into the past! Keep it real, man!

t = -30/-4 = 7.5 hours

Now, in what I wrote, “t” is the time of the first cyclist. t – 3, or 4.5 hours is the time from when the second cyclist starts to when he catches up. I ain’t too sure, the way the question’s worded, which time it wants. Read the original again an’ see if you can figure it out… is it from when the first guy starts or from when the second guy starts?

Now, the time seems pretty reasonable, but…. let’s check. First cyclist goes for 7.5 hours at 6 mph, that’s 45 miles. Second cyclist goes for 4.5 hours at 10 mph, that’s 45 miles, too. There’s your answer. It’s 7.5 hours from when the first guy started, and 4.5 hours from when the second guy started. There ya go.

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.

A room is 24 feet long, 18 feet wide, and 9 feet high. How many square yards of wallpaper are needed to paper the four walls of the room?

You got your basic area problem, right? How do I know it’s “area”? Well, area is the space on the surface of something. Like, how much carpet covers a floor, or how many tiles on a bathroom wall. Or paint on a room. If you’re covering a surface, you’re talkin’ area. Now, how to solve it?

You got a few bumps in the road. First, you got dimensions in feet, an’ you want an answer in yards. Whenever you got different measurements in a problem, I recommend always changin’ everything to the dimensions you want in yo’ answer first off. That means, changin’ all the feet to yards. Now, there’s three feet in a yard, and dat’s jus’ somethin’ you got to know. So, to change feet into yards, divide by 3.

24 feet = 8 yards
18 feet = 6 yards
9 feet = 3 yards

Hey, you gotta know you’re on the right track when all the numbers divide out evenly! Too bad real life don’t work dat way. ‘k. So’s, now it’s important to picture what the question’s about, specially with this kinda dimension question. You got a room, 8 yards by 6 yards, and 3 yards tall.

What’s the area of the 4 walls? That’s the real question… a wallpaper or carpet or tile (or anything that goes on a flat surface) question is an area question.

So… each wall got the same height, the height of the room…3 yards (9 feet):

wall 1: 3 yards × ?
wall 2: 3 yards × ?
wall 3: 3 yards × ?
wall 4: 3 yards × ?

So, what’s the width of the walls? well, 2 walls is 8 yards long (the two walls opposite of each other on the sides of the room that’re 24 feet) and 2 walls is 6 yards long (the two walls opposite of each other on the sides of the room that’re 18 feet).

wall 1: 3 yards × 8 yards
wall 2: 3 yards × 8 yards
wall 3: 3 yards × 6 yards
wall 4: 3 yards × 6 yards

To find the area, multiply:

wall 1: 3 yards  × 8 yards = 24 square yards
wall 2: 3 yards  × 8 yards = 24 square yards
wall 3: 3 yards  × 6 yards = 18 square yards
wall 4: 3 yards  × 6 yards = 18 square yards

And to find the total, add:

24 + 24 + 18 + 18 = 48 + 36 = 84 square yards

Answer’s 84!

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.

I’m not bad in math except when it comes to word problems any advice?

Hey, the GED’s real big on word problems, so you gotta get the hang of them. Why’d they gotta have word problems? Cuz they ain’t so much int’rested if you can figure out 3x + 4 = 12 as if you can figure out how much you’ll save each month if you buy generic soda instead of regular soda. See what I mean? One’s a plain math problem, the other’s a word problem. You’ve gotta first figure out what math you need to use it! See, my math teacher told me, math’s like a tool box. You got all these different math tools, and they help you do different things. You gotta know when to use what tool, to solve the problem you got in front of you. So, a math word problem is like a real-life problem that you might use math to solve. Okay, okay, whatcha really wanna know is, how to solve ‘em?

1) Read the Problem and Figure Out What It’s Asking

The first step is to figure out what the answer you’re lookin’ for is. How ’bout that question I asked before?

Greg buys 4 2-liter bottles of brand-name soda a week, at the price of $1.29 per bottle. One week each month, the soda goes on sale for $.79 per bottle. The store also has generic soda, which always costs $.99 per bottle. How much will Greg save in one year by buying the generic soda instead of brand-name soda?

There’s a word problem for ya’. So, read it through. What’s the main idea? What’s it asking? What is it you’re trying to find? In this place the answer is savings, in one year, of buying generic soda. It can help you out to rewrite what you’re trying to find in your own words:

Find the savings, in one year, of buying generic soda.

2) Look at What Information You’ve Got

Go through the problem and make notes of what information it gives you. This is what you’ve got to work with. I might go through the problem an’ pick out:

2-Liter Sodas Bought: 4 bottles a week
Costs: $1.29 each, $.79 once a month for 1 week
Generic Costs: $.99 each

Sometimes it helps to draw a picture or a chart. Anything that helps you get the info straight in your head.

3) Make a Plan

Now you gotta figure out what to do. How do you take the info it gives you, an’ get from there to the answer? This is where thinkin’ it through comes in. You need a plan. You got all the tools in your math toolbox: addition, subtraction, multiplication, division. Which ones make sense? What info do you need to use?

Well. Let’s look at it, one step at a time. We wanna know how much he’ll save in a year. So, how much does he spend in a year? Let’s start there. Then, we’ll figure out how much he’ll spend if he buys generic. Then, we want to know the difference of the two. That means, subtracting. So, that’s my plan:

1) Figure out how much Greg spends in a year.
2) Figure out how much Greg would spend buying generic.
3) Subtract to find out how much he’d save.

3) Do the Math!

Step 1: How much does he spend in a year? Greg buys 4 sodas a week. Most of the time, they’re $1.29 each. To figure out how much he spends most weeks, what do you do? Multiply, right? $1.29 times 4 sodas:

4 × 1.29 =5.16

Okay, that’s a regular week. What about when the soda’s on sale? That’s:

4 × .79 =3.16

Now, you need some more thinking. How many weeks in a year does he spend $3.16? Once a month, right? So that’s 12. For each of 12 weeks, he pays $3.16. Multiplication again:

3.16 × 12 =37.92

Now, that’s part of the year. The rest of the year, he pays 5.16. Now, to know how many weeks that is, you (1) need to know there’s 52 weeks in a year, and (2) need to subtract, because you want to know how many are left.

52 – 12 = 40

So, for 40 weeks, he spends $5.16:

40 × 5.16 =206.40

Great. Long road to get here. But what’s the total he spends in a year? When you want to know a total, you want to add…

206.40 + 37.92 = 244.32

Yikes! That’s a lot of dough. (Hey, most GED problems won’t have so many steps, but it’s good practice.)

Step 2: How much would he spend buying generic? This is easier, cuz it’s all one price. $.99 times 4 bottles times 52 weeks.

.99 × 4 × 52 = $205.92

Step 3: Subtract to find out how much he’d save:

$244.32 – 205.92 = $38.40

4) Does the Answer Make Sense?

Okay. Take a step back. Does what you did make sense? Does it seem like a reasonable answer to the question? The question is, how much will he save in a year if he buys generic soda, about .30 cents less (usually) than brand-name soda–but sometimes .20 cents more. So, on average, what’s he saving? .20 per soda? Maybe? 50 weeks, 4 sodas a week, so 200 sodas-ish a year, at 20 cents would be about 40 bucks.  The answer’s about 40 bucks. That sounds reasonable. I ain’t bein’ exact enough to estimate an answer, but I know my answer at least ain’t way off in the wild somewhere. I mean, if I got $384.00 by accident, I’d KNOW it was wrong.

The other advice I got is, practice! Here’s some places to get practice word problems. Hey, they won’t all be this complex. Start with the easier ones an’ work yo’ way up. An’ show me any of ‘em that give you problems. I’ll try walkin’ thru ‘em.

http://www.mathplayground.com/wordproblems.html

http://www.quia.com/pop/13193.html

http://www.quia.com/jq/19998.html

http://www.cdli.ca/CITE/math_problems.htm

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.

Satix is at a flea market. She wants to get the most knives at the lowest price. But she also wants to get at least one of each. The prices of the knives are: $ 4.30, $12.80, $11.50, $7.30, $ 7.50. If she has $50 to spend how much will her change be?

This is a tough word problem, so you gotta think it through. Hey, it’s great practice. Cuz if you can think through this, thinkin’ through some other word problems’ll be E-Z. This is what I call a number sense problem, cuz there ain’t no real advanced math, just makin’ sense of it, bein’ logical about it, and doin’ some basic math.

So, Satix wants one each of all the knives. You know she’s gonna buy one of each, so she’s going to buy at least:

$ 4.30 + $12.80 + $11.50 + $7.30 + $ 7.50 = $43.40

She’s spent $43.40, just on one of each knife. But she wants as many knives as possible. So, does she buy anything else? How much’s she got left?

$50.00 – $43.40 = $6.60

She’s got $6.60 left, so she can buy one more of the cheapest knives.

$6.60 – $4.30 = $2.30

That gives her $2.30 in change. Not enough to get another knife. So she be done. And you got the answer to the question…how much change she got left? $2.30. There ya go.

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.

If Rob flips 3 coins what is the chance that they will come up all tails?

The correct answer was : 1/8 , but it doesn’t make sense to me ! can you explain why it is 1/8 ?

First things first. To find the probability of ONE thing happening, you’ve got to figure out how many times the thing you’re asking about will happen, and put that over how many times anything will happen. Flipping a coin is pretty easy. It could come up heads, or it could come up tails. There are two possibilities, and one chance that it’ll come up tails one out of two.

Probability of tails on one coin flip = 1/2

That’s the total number of possibilities it’ll come up tails over the total number of possibilities, altogether. Got it?

Now, you’ve got to figure out, separately, the probability that it’ll come up tails EACH of the three times. That’s simple. They’re all the same. The chance is 1/2 that it’ll come up tails each time you flip the coin. So you got three 1-in-2 chances.

First try: 1/2

Second try: 1/2

Third try: 1/2

How do you figure out what the odds are of it coming up tails all three times? Multiply! Remember, to multiply fractions, multiply all the top numbers to get the top number and multiply all the bottom numbers to get the bottom number:

1/2 × 1/2 × 1/2 = 1/8

There’s 1/8 chance of it coming up tails three times in a row.

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com

3x = 7 – 4x

You wanna figure out what “x” is equal to The problem comes in when you have a number befo’ the x, and need to get all the “x”es on the same side. Think of it this way… you don’t just got one x, you got four x’s. So, you gotta move all 4 x’s to the other side. In other words, think of “4x” as all going together.

3x = 7 – 4x

Add 4x to both sides to get rid of the x’s on the right…because you have to get rid of all four x’s.

3x + 4x = 7 – 4x + 4x

The -4x and the +4x cancel each other on the right side… and on the left, 3x + 4x = 7x. Think of it like that’s how many x’s you got… 3 x’s (x +  x + x) plus 4 x’s (x + x + x + x) gives you 7 x’s (x + x + x + x + x + x + x).

7x = 7

Now, if the 7 goes with the x, how do you get rid of it? You can, because what it’s really saying is 7 times x. 7 times x is the same as (x + x + x + x + x + x + x) is the same as 7x. Just like 7 times 3 is the same as (3 + 3 + 3 + 3 + 3 + 3 + 3), and could be written 7(3). Divide by 7 on both sides to get:

x = 1

Let me know if this gives you any more problems!

For more information about the GED test and GED test preparation, visit the GED Academy at http://www.passGED.com.