Question

How do you solve `3:12 = x:16`?

Answer 1

x = 4

Explanation:

We can express the ratios as fractions.

`rArr3/12=x/16`

Solve for x by `color(blue)"cross-multiplication"`

`color(red)(3)/color(blue)(12)=color(blue)(x)/color(red)(16)`

multiply the same colours across (X) the fraction.

`rArrcolor(blue)(12x)=color(red)(3xx16)=color(red)(48)`

now we have to solve : 12x = 48

divide both sides by 12

`(cancel(12)^1x)/cancel(12)^1=cancel(48)^4/cancel(12)^1rArrx=4`

That is 3:12 = 4:16 = 1:4 'in simplest form'