Question

Frankie solved the math problem below. Find the error in Frankie's work and explain it in words, using math language. 2 1/3 - 1 2/5 2 1/3 x 5/5 = 2 5/15 -1 2/5 x 3/3 = -1 6/15 = -1 1/15

Answer 1

Given:

The expression is

`2(1)/(3)-1(2)/(5)`

To find:

The error in Frankie's work.

Solution:

We need to simplify
`2(1)/(3)-1(2)/(5)`, so

`2(1)/(3)=2(1)/(3)* (5)/(5)`

`2(1)/(3)=2(5)/(15)`

and,

`1(2)/(5)=-1(2)/(5)* (3)/(3)`

`1(2)/(5)=-1(6)/(15)`

Now,

`2(1)/(3)-1(2)/(5)=2(5)/(15)-1(6)/(15)`

`2(1)/(3)-1(2)/(5)=(2+(5)/(15))-(1+(6)/(15))`

`2(1)/(3)-1(2)/(5)=2+(5)/(15)-1-(6)/(15)`

`2(1)/(3)-1(2)/(5)=1-(1)/(15)`

`2(1)/(3)-1(2)/(5)=(14)/(15)`

Therefore, there is error in Frankie's last step. In that step, he did not subtract the mixed fraction correctly.