8 is to 64 as 2 is to x

Solve `8/64=2/x` .

(1) One
method is to cross multiply and divide. (The product of the means is equal to the
product of the extremes). Thus 8x=2(64).

Then 8x=128, and
x=16.

(2) Another method is to
simplify the left-hand side-- thus 8/64=1/8.
`1/8=2/x` . Multiply the
left-hand side by 2/2 to get `2/16=2/x` . Since the numerators are equal, the
denomiators will be equal so x=16.

When you write 8 is to
64, you are writing a ratio, the same as 8:64 or 8/64.