How do you solve proportions with a variable?

Answer 1

Note: When I say number, I am also including variables and variables with a coefficient (terms).

You Have to Cross-Multiply, and then solve algebraically.

Lets say you have a problem like this: x/2=2/8

# Multiply the Top Left number with the Bottom Right number, and put it on one side of an = sign # Multiply the Bottom Left number with the Top Right number, and put it on the other side of the = sign.

In our case, multiply the inner numbers and put them on one side of an = sign, and then multiply the outer numbers and put them on the other side of the = sign.

In our case, you get: 2*2 = 8x

4 = 8x

4/8 = x

.5 = x

So there you have it, x=.5