Add 20/28 and 70/15
1st number: 20/28, 2nd number: 4 10/15
20/28 + 70/15 is 113/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
20/28 = 20 × 15/28 × 15 = 300/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
70/15 = 70 × 28/15 × 28 = 1960/420 - Add the two like fractions:
300/420 + 1960/420 = 300 + 1960/420 = 2260/420 - 2260/420 simplified gives 113/21
- So, 20/28 + 70/15 = 113/21
In mixed form: 58/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/28+70/15 20/56+70/15 20/28+70/30 60/28+70/15 20/84+70/15 20/28+70/45 20/28+70/75