Jesse writes:I was wondering If u could let me know if I got these two questions correct I’m taking my ged next week & I want to feel comfortable with this math.

On a map 1/3 in=15 miles find the distance between two towns on a map that equals 3 2/3 in. How many miles r between the two? my answer was 75 miles am I correct?Next QuestionThe scale on a map indicates that 1/2 inch represents an actual distance of 120 miles, how far apart will two towns be if the actual distance between them is 180 miles my answer was 2 inches am I correct? if not could u explain how to set up these type of problems? thank you, Jesse.

Jesse,

Hey! Congrats on your GED test comin’ up. Y’know what these questions are? Ratios. I got a ratio post on my blog at: http://www.passged.com/student_blogs/curtis/2007/12/24/rice-ratios-gotta-love-that-ged-math/

There’ll prolly be a ratio question on the GED test. Here’s how it works. Take the first question. You got 1/3 inch, that equals 15 miles. Picture it in your head. Say this line is 1/3 inch: |—| It be 15 miles.

So, you got to find out how many miles in 3-2/3 inch. Well, first you gotta find out, how many 1/3-inches are in 3-2/3 inch. Get it?

Three 1/3-inch lengths are in 1 inch, like this:

|—|—|—|

So, in 3-2/3 inches, there’s 11 1/3-inch lengths:

|—|—|—|

|—|—|—|

|—|—|—|

|—|—|

Each 1/3-inch is 15 miles, right? So, we got 11 lengths of 15 miles… that’s 15 times 11, and that’s 165 miles! There ya go. Always makes it easier to understand to picture it in your head.

If you want to do it mathematically, what I did was set up a ratio:

1/3:15

3-2/3:x

Divide 3-2/3 by 1/3… then multiply 15 by the answer to get x.

Here’s the other one.

1/2 inch = 120 miles

x = 180 miles

Same deal here, right? You got a ratio.

1/2 inch:120 miles

x:180 miles

The relationship between 120 and 180 got to be the same as between 1/2 and the answer. So, what’s the relationship between 120 and 180? If you divide 180 by 120, 180/120 = 18/12 = 9/6 = 3/2 = 1-1/2

So, 180 is 1-1/2 times 120. Then x got to be 1-1/2 times 1/2. That’s 3/4. If it’s easier, you can do 1.5 x .5 = .75 …same thing. So, the answer’s 3/4 inch. Get it?

Hope this helps!

Curtis

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

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Hey Curtis

I need your help again. on s ratio problem

the quesion is Juanite take home $1,800 each month. Her empoloyer withholds $600.00 each month for taxs and other withholding.

A what is the ratio of amount that withhold from Juanita’s salary to take home pay?

B what is the ratio of the amount that is withheld from Juanita’s salary to her total earning?

how can i slove this problems

Yo Christina,

Ratios be just like fractions. So, if it asks, “What is the ratio of “amount withheld” to “take home pay,” you can just replace the “to” with a colon. Like “amount withheld” : “take home pay” which would be 600:1,800.

Then you just gotta simplify. You can take out the two zeros and end up with 6:18 to make it easier. Can 18 be divided by 6? Yeah, three times, and 6 can be divided by 6 once. So the answer to A is 1:3.

B is a little trickier, right? They don’t tell you everything upfront, so you gotta do some math first. So, the ratio this time is “amount withheld” : “total earnings.” We know that the first number’s gonna be 600 again, but how do we know what her total earnings are?

Her total earnings be EVERYTHING she makes, including the amount that’s withheld. So you just gotta add up her take home and withheld. 1,800 + 600 = 2,400. So the ratio be 600:2,400. Simplify to 6:24, then again to 1:4.

Make sense?

Oh! I got it thanks