A 12lb turkey at the grocery store costs $13.50 and feeds 8 people. A pint of potato salad costs $3.50 per pint, and one pint can feeds about 3 people. A large can of yams is on sale for $4, and that feeds 5 people. Finally, a pumpkin pie feeds about 6 people and costs $4.99. Paula is shopping for Thanksgiving and is planning on having 16 guests, including herself. How much will it cost to make sure there is enough of each item for everyone?

This is the kinda question that shows how Math can be practical for everyday use, right? I’ve never bought thanksgiving dinner myself, but sometimes you get some friends comin’ over for some pizza and beers, and you gotta know how much to buy for everyone (and how much you charge them at the door).

So first thing I gotta do here is write out all the information, to make sure I get what they’re askin’.

Paula’s got 16 people comin’ for dinner. First I gotta break down the problem and see how many people each type of food feeds. I’ll make a quick list.

12lb Turkey – $13.50 – Feeds 8

Potato Salad – $3.50 – Feeds 3

Yams – $4.00 – Feeds 5

Pumpkin – $4.99 – Feeds 6

Once I got all this information laid out, it’s pretty simple to figure things out:

The turkey feeds 8, and we know that 8 × 2 is 16, so that’s easy. She needs 2 turkeys. That’s $27.

A pint of potato salad feeds 3, so she’d need 6 pints to feed 16 since 3 × 6 = 18. 3 × 5 is only 15, and that wouldn’t be enough salad for everyone. So then I gotta times 6 × 3.50 to get $21

She’d need 4 cans of yams, so that’s $16, and 3 pumpkin pies. That’s $14.97. Usually I’d just round the pie up to $5, which makes it an easy $15, but since we gotta have the exact answer here, I can’t do that. So adding up all those answers, I got $78.97. Damn, that’s expensive. And it ain’t even including no drinks. See, that’s why I never have no Thanksgiving at my place. Gotta clean it all up too, no way. I just go out to a buffet and pay like ten bucks for all I can eat. That’s how you do it, yo.

Have a good Thanksgiving y’all.

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

I used to work in a machine shop. Sometimes I would have to convert fractions to inches like 1/3. I know how to do that, all you have to do is divide 1 by 3. The question is, I always had to use a calculator, and I would like to do that without using a calcualtor. Every time I tried I would’nt get the proper answer. How do you do that without using a calculator.
Mark

Yeah, that’s the key, Mark. Doin’ stuff in your head makes it easier and faster, an’ helps a lot on the GED. Part of it is jus’ knowin’ or rememberin’ some of the fractions you see all the time.

Think of it in terms of dollars and cents to remember the real easy ones:

1/4 (a quarter) = 25 cents or .2

1/2 (half dollar) = 50 cents or .5

3/4 (three quarters) = 75 cents or .75

1/10 (a dime) = 10 cents or .1

Tenths are easy. It’s always gonna be point-whatever-is-on-top:

2/10 = .2

3/10 = .3

4/10 = .4

5/10 = .5

6/10 = .6

7/10 = .7

8/10 = .8

9/10 = .9

Fifths is always point-the-top-number-times-2.

1/5 = .2

2/5 = .4

3/5= .6

4/5 = .8

Then, there’s the thirds. These are pretty easy to remember, but they don’t give even numbers:

1/3 = .3333 (remember the 3 from 1/3)

2/3 = .6667 (remember that 2 x 3 = 6)

Then, there’s eighths.

1/8 = half of a quarter = .125 (you can remember it cuz 12 is kinda like 1/2 and 25 is a quarter)

2/8 = 1/4 = .25

3/8 = 1/8 + 2/8 = .125 + .25 = .375

4/8 = 1/2 = .5

5/8 = 1/2 + 1/8 = .5 + .125 = .625

6/8 = 3/4 = .75

7/8 = 3/4 + 1/8 = .75 + .125 = .875

Then, what about more complicated ones? You can still do ‘em in your head. You gotta divide the bottom number into the top, so like 2 into 1 = .5 … on harder ones, it’s harder to do in your head.

Say you have 11/25 … you gotta divide 25 into 11… Start by adding a zero to the 11. So you got 25 into 110… 25 goes into 100 four times, so you got a 4… and ten left over. Add another zero… and that’s 25 into 100 again… that’s 44. Now, where’s the decimal go? Well, it’s before the first number, .44 … you can check it by thinking, 11/25 is almost a half, and .44 in almost .5. So you’re good.

Another way is to try to make the bottom number 100. So, 11/25 = 44/100. Then you take the top number and move the decimal place 2 points, so 11/25 = .44

Here’s some places to go for some more explanation and practice:

http://www.mathsisfun.com/converting-fractions-decimals.html

http://www.curiousmath.com/index.php?name=News&file=article&sid=77

http://www.learningwave.com/chapters/decimal13/basics/convert.html

http://www.coolmath.com/decimals/04-decimals-converting-fraction-to-decimal.html

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