Add 15/75 and 21/30
15/75 + 21/30 is 9/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 30 is 150
Next, find the equivalent fraction of both fractional numbers with denominator 150 - For the 1st fraction, since 75 × 2 = 150,
15/75 = 15 × 2/75 × 2 = 30/150 - Likewise, for the 2nd fraction, since 30 × 5 = 150,
21/30 = 21 × 5/30 × 5 = 105/150 - Add the two like fractions:
30/150 + 105/150 = 30 + 105/150 = 135/150 - 135/150 simplified gives 9/10
- So, 15/75 + 21/30 = 9/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/75+21/30 15/75+42/30 15/75+21/60 45/75+21/30 15/75+63/30 15/75+21/90