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!

Algebra’s like a puzzle. Know those puzzles where you gotta move the pieces around to make a picture? It’s like that. To find what number “x” is, you gotta move the numbers around, so that “x” is by itself on one side. And there’s rules. Here’s the key: you have to do the same thing to both sides of the equation.

So, if x + 3 = 5 and you want x by itself, you’ve got to “zero out” the + 3. To make the + 3 cancel out, you’ve got to subtract 3. That means you’ll have 3 – 3 on the side with the x, and 3 – 3 is 0, and 0 is nothing. That’s what you want… nothing with the x.

But, if you want to subtract 3 from the left side, you gotta subtract 3 from the right, too, to keep ‘em equal.

x + 3 = 5
x + 3 – 3 = 5 – 3
x + 0 = 2
x = 2

Okay, that’s the easy part. Hard part is, if you got x’s on both sides.

2x = x + 5

What do I want to do? Subtract x from both sides, to get rid of the x on the right (x – x is the same as 3 – 3 or 23 – 23…. it’s zero).

2x = x + 5
2x – x = x – x + 5
2x – x = 0 + 5
2x – x = 5

Now, what’s 2x – x? The shorthand rule is, you subtract (or add) the numbers by the x’s, and leave the x alone. “x” without a number has an invisible “1″ next to it. So:
5x – 3x = 2x
22x + 5x = 7x
x + x = 2x
5x – x = 4x

That means, if 2x – x = 5, then x = 5.

Here’s why. 5x means 5 times x. And 5 times x means x + x + x + x + x. That’s what multiplication is, a shorthand way to add a number plus itself a bunch of time.
5 × 9 = 9 + 9 + 9 + 9 + 9
5x = x + x + x + x + x

So, 2x – x means x + x – x. Two of the x’s cancel out (x – x = 0). So, it’s x + 0, or just plain x.

2 x’s minus 1 x is… 1 x. Just like if you got 2 apples and take away 1 apple, you got one apple left.

So, here’s a problem:

5x + 14 = 3x + 22

I can subtract 14 from both sides to move all the numbers to the right…
5x = 3x + 8

Now, I can subtract 3x from both sides to move all the x’s to the left…
2x = 8

The last step, since x is multiplied by 2, is divide both sides by 2 to get the x by itself….

x = 4

There ya go!

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.

See, it’s a scientific calculator with all kindsa cool functions that you don’t need on the test. It’s important to know how to use it so you don’t hit the wrong order of buttons and get the wrong answer. And the better you gonna get with the calculator, the faster you can do the math.

Hey, these things only cost bout 10 or 15 bucks. So, go get yo’self one, first off, to practice at home. Here’s a link to buy it on Amazon: Casio fx-260 Solar Calculator

Case ya don’t got one, here’s what it looks like:

So, here’s the most important stuff:

Press “on” to turn it on. Yeah, I know, basic, right? It’ll say “DEG” in the top of the screen. Don’t worry what it means, if it says “DEG,” you’re in the right mode to do regular math. But if it says somethin’ else, press “mode” and “4″ to get it to say “DEG”. Now you set!

Jus’ always press “ON” or “AC” to start a new problem, so you know your memory’s clear. Havin’ the last number from the last problem in memory’s gonna mess you up.

To do basic math, jus’ put in the math problem like it’s written “5 + 8 × 16″ or “29 × (4 + 200)”, or whatever, and press the equal key at the end to get the answer.  Remember: you got to press the equal key to get the answer!!!

It knows the order of operations, that is, like, what to do first in the problem. So, it’ll do (1) things in parenthesis, then (2) multiplication an’ division, then (3) addition and subtraction. So, if you’re fixin’ up 9your own equation to punch in, remember–that’s the order it’s done in. You type in parenthesis along with all the rest of your problem. Them’s the [(--- and ---)] keys, for the open and close parenthesis.

Now for the things that are different than just typin’ in the problem:

To get a square root, type in whatever you want the square root of, then “shift” (top left) then the key with x² on it, then equal to get the answer. To get a number squared, just type in the number and then press the x²key and equal.

To make a number negative, press the “+/-” key AFTER the number. So, to type in -9, type “9″ “+/-”

That’s the basics! Now, here’s some links to learn more:

http://www.ilc.org/cfmx/GED/GED_sample_m2.cfm?Menu_ID_Sel=35200&Lang_Sel=1
http://www.ket.org/GED2002/Mathcalc/Mathcalc1.htm

For more information on 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.

Hey there! Algebra’s got a lot of stuff in it, and it takes a while to learn. You can look at a lot of the algebra articles here: http://www.passged.com/student_blogs/curtis/category/algebra/. Here’s the absolute, need-to-know’s:

1) Gotta understand the idea of a variable. A variable is a letter or symbol that stands for something unknown or something that can change. A lot of the time, you’ll see “x” used as a variable: x + 5 = 10 … why do you use a variable? Cuz you want to figure something out, and to put the “something you don’t know” into a math equation you need some sort of symbol for it. That’s where the x comes in. You’ll need to be able to understand what 2x means (2 times x) and mutliply, add, and subtract with variables to move them around.

2) Gotta understand how to move numbers around in an equation. In an equation, you can add the same number to both sides, subtract the same number from both sides, multiply both sides by the same number, or divide both sides by the same number (as long as it’s not zero). Why do you want to do that? So you can move all the numbers to one side, and the variable to the other, and figure out what the variable equals. So, for x + 5 = 10, you can subtract 5 from each side. Then, x = 5. Easy.

3) Gotta be able to see what an equation means in real life. So, take a word problem and make an equation out of it.

4) Understand inequalities, like 4 < 2x or x +5 > 10.

5) Gotta know how to deal with negative numbers and fractions. Why? These are the main things that’ll mess you up in moving around numbers. Better you understand them, the better you’ll do.

6) Helps to know about exponents, like x². You won’t get into real high exponents, jus’ understand what “squared” means (something times itself) and what a square root means.

7) Helps to know about graphing a line… like what’s a slope? How do you get a line on a graph from an equation?
The hardest part is quadratic equations (you can see my article ’bout them). But there’s not gonna be a lot about them on the GED, so no big sweat.

Dat’s the basics. I know it’s a lot, an’ I can’t promise my website covers it all. But your son can always write in to me with special problems if he’s havin’ trouble with something. It’s hard to study on your own, so I totally recommend the GED Academy study program at http://www.passGED.com. It’s got a real complete math course, and if he has a problem he can call up an instructor for help.

http://www.teachertube.com/view_video.php?viewkey=ebd7c1e1b7118af88edc&page=1&viewtype=&category=