Add 70/42 and 90/28, Solve 1 28/42 + 3 6/28 as a fraction

Add 70/42 and 90/28

1^st number: 1 28/42, 2^nd number: 3 6/28

70/42 + 90/28 is 205/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
70/42 = 70 × 2/42 × 2 = 140/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84
Add the two like fractions:
140/84 + 270/84 = 140 + 270/84 = 410/84
410/84 simplified gives 205/42
So, 70/42 + 90/28 = 205/42
In mixed form: 437/42

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad