How do you solve \frac { x } { 900} = \frac { 35} { 15}?

3 Answers
Dec 1, 2017

x= 2100

Explanation:

First cross multiply to have a linear equation:

15x = 900*35
15x= 31500

To isolate x, divide by 15:

x = 31500/15

x= 2100

Dec 1, 2017

The easiest way to do this is to cross multiply and set the equation up like

15x=900*35

Explanation:

Think of it like you're multiplying 15 to both sides, which gets rid of the fraction on the right side (because 15/15=1). This also works for the left side when you multiply each side by 900.

After you get

15x=31500

simplify it by dividing each side by 15 to get

x=2100

Dec 2, 2017

x=2100

Explanation:

In " "x/900 = 35/15" " you need to isolate x

Multiply both sides by 900 to cancel the fraction with x

(color(blue)(900xx)x)/900 = (color(blue)(900xx)35)/15

(cancel900xxx)/cancel900 = (cancel900^60xx35)/cancel15" "larr simplify

x = 2100

In this case I would not use cross-multiplying because it changes a 1x term into a 15x term, which then has to be divided by 15