Question

Margaret's bottle of shampoo is seven eights phone. She uses 1/3 of the shampoo in the bottle to wash the dog. Estimate what fraction of shampoo is left. Use whole numbers in benchmark fractions to explain.

Answer 1

Fraction of shampoo left =
`(13)/(24)`

Solution:

Given fraction of full shampoo
`=(7)/(8)`.

Fraction of shampoo Margaret used
`=(1)/(3)`

Fraction of shampoo left = Full shampoo – fraction of shampoo used

`$=(7)/(8)-(1)/(3)$`

To make the denominators same do cross multiplication.

`\begin{aligned}&=(7 * 3)/(8 * 3)-(1 * 8)/(3 * 8)\\&=(21)/(24)-(8)/(24)\\&=(21-8)/(24)\\&=(13)/(24)\end{aligned}`

Hence
`$(13)/(24)$` of the shampoo bottle is left.