Question

Seventh grade L.10 Percent of change: word problems 545 You have At his most recent medical checkup, a boy was 45 inches tall. Currently, he is 20% taller. How tall is the boy now? inches Submit

Answer 1

54 inches

Explanation

you can easily solve this by using a rule of three

let x represents the current heigth of the boy, then

if

`45\text{ inches}\rightarrow100\text{ \%}`

then

`x\rightarrow120\text{ percent}`

as the proportion is the same:

`\begin{gathered} (45)/(100)=(x)/(120) \\ Multiply\text{ both sides by 120} \\ (45)/(100)\cdot120=(x)/(120)\cdot120 \\ 54=x \end{gathered}`

so, the answer is 54 inches.

I hope this helps you