Question

Eliza’s backpack weighs 18 7/9 pounds with her math book in it. Without her math book, her backpack weighs 14 ⅞ pounds. How much does Eliza’s math book weigh?

Answer 1

Make each fraction have a like denominator

7/9 * 8/8= 56/ 72

7/8 * 9/9 = 63/72

18 + 14 + (56+63)/72

32 + 119/72

32 + 1 + 47/72

33 and 47/72

Answer 2

The Eliza's math book weigh =
`3(65)/(72)`.

Explanation:

We are given that

Eliza's backpack weighs with her math book =
`18(7)/(9)=(169)/(9)`

Eliza's backpack weighs without her math book=
`14(7)/(8)=(119)/(8)`

We have to find the Eliza's math book weigh.

Therefore, we subtract the Eliza's backpack weighs without her math book from the Eliza's backpack weighs with her math book.

Eliza's math book weighs= Eliza's backpack weighs with her math book - Eliza's backpack weighs without her math book

Eliza's math book weighs =
`(169)/(9)-(119)/(8)`

Eliza's math book weighs=
`(169* 8-119* 9)/(72)`

Eliza's math book weighs=
`(1352-1071)/(72)`

Eliza's math book weighs=
`(281)/(72)`

Eliza's math book weighs=
`3(65)/(72)`

Hence, the Eliza's math book weighs=
`3(65)/(72)`.