Question

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

Answer 1

`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`

Answer 2

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`

Answer 3

`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`