Thread: Fraction Problems

I don't get these problems, can someone help me out?

1. Jeff added two fractions. Lydia subtracted the same two fractions. Jeff's answer was 3/4 greater than Lydia's. What could the fractions be?

2. To calculate 7 1/8 - 2 2/3, Lee added 1/3 to 4 1/8. Why do you think that Lee did this?

The answers/solutions/equation to these are simple but I can't seem to get a hold of them please help. Thank you!

Originally Posted by puppy_wish

I don't get these problems, can someone help me out?

1. Jeff added two fractions. Lydia subtracted the same two fractions. Jeff's answer was 3/4 greater than Lydia's. What could the fractions be?

2. To calculate 7 1/8 - 2 2/3, Lee added 1/3 to 4 1/8. Why do you think that Lee did this?

The answers/solutions/equation to these are simple but I can't seem to get a hold of them please help. Thank you!

1. Let the fractions be x and y.

x + y = z .......................(1)
x - y = z - 3/4 ................(2)

=> 2y = 3/4
=> y = 3/8

so x + 3/8 = z .........................(3)
and -x + 3/8 = z - 3/4 ..............(4)

=> 2x = 3/4
=> x = 3/8

so the fractions are x = y = 3/8


2. To calculate 7 1/8 - 2 2/3, Lee added 1/3 to 4 1/8. Why do you think that Lee did this?

2 2/3 is almost 3. so what Lee did was to subtract 3 from 7 1/8 to get 4 1/8. But now, since 2 2/3 is actually not 3, he had to make up for subtracting a greater number by adding the difference. (the difference between 2 2/3 and 3 is 1/3).

thank you soooooooooooooooooooooooooo much!!!

Originally Posted by puppy_wish

thank you soooooooooooooooooooooooooo much!!!

you're very welcome. good luck with your class. i have one of my own to go to now. so catch you later