How do you change fractions to have like denominators?

Answer 1

by multiplying any single thing by either (1/1, 2/2, 3/3, 4/4, etc.). If you have any fraction, say (1/2), and multiply it by any fraction with form (n/n) you will have the same number, just in a different form. (1/2 * 2/2) = (2/4) = (1/2)

BECAUSE: 2/2 = 1/1 = 3/3 = 4/4.

So to get like denominators with:

(1/2) + (3/8)

you just multiply (1/2) by (4/4) to get (4/8)

esentially you're multiplying 1/2 by 1, but (4/8) is easier to add to (3/8), which equals (7/8).

If you have something more complicated like:

(3/5) + (1/4)

since neither of the fractions is a multiple of the other, a simple procedure is to "CROSS MULTIPLY" which has you multiply both the numerators of either fraction by the other's denominator, then multiplying the denominators together.

essentially you're multiplying both fractions by (1/1, 2/2, 3/3, etc.).

((3/5)*(4/4)) + ((1/4)*(5/5))

which turns into

(12/20) + (5/20) = (17/20)