Question

Create a proportion using the form %/100 = is/of = to represent the following word problem. 78% of what number is 42?

Answer 1

.78 x = 42

x = 42 / .78

The number is 53.8461538462

Explanation:

Answer 2

`x\approx 53.85`

Explanation:

If 78% of x (some number) is equal to 42, then We must set this as an equation to find it.

1) Rewriting 78% as a fraction. And considering that when We say 78% of some number (x) we mean a product.

`78\%=(78)/(100)\Rightarrow (78)/(100)x=42`

2) Then we can go on:

`100*(78)/(100)x= 42*100\\\\78x=4200\\ \\(78x)/(78)=(4200)/(78)\Rightarrow x\approx 53.85\\`

3) Alternatively, simply dividing 42 by 0.78 (78%) would come to the same result:

`(42)/(0.78)\approx 53.85`