Question

Kwesi is putting on sunscreen. He uses 3ml to cover 45 cm2 ​​ of his skin. He wants to know how many milliliters of sunscreen g he needs to cover 240 cm2 ​​of his skin. He assumes the relationship between milliliters of sunscreen and area is proportional.

Answer 1

The answer is
`16\ ml`

Explanation:

we know that

He uses
`3\ ml` to cover
`45\ cm^(2)` ​​ of his skin

so

by proportion

Find how many milliliters of sunscreen are needed to cover
`240\ cm^(2)`

`(3)/(45)(ml)/(cm^(2)) =(x)/(240)(ml)/(cm^(2)) \\ \\x=240*3/45\\ \\ x= 16\ ml`

Answer 2

16 ml. If you set 3/45 = x/240 where x is the amount he needs for 240ml^2, then cross multiply and divide to find x you get 16