Add 15/21 and 30/7
1st number: 15/21, 2nd number: 4 2/7
15/21 + 30/7 is 5/1.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
15/21 = 15 × 1/21 × 1 = 15/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
30/7 = 30 × 3/7 × 3 = 90/21 - Add the two like fractions:
15/21 + 90/21 = 15 + 90/21 = 105/21 - 105/21 simplified gives 5/1
- So, 15/21 + 30/7 = 5/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+30/7 15/21+60/7 15/42+30/7 15/21+30/14 45/21+30/7 15/21+90/7 15/63+30/7 15/21+30/21 75/21+30/7 15/21+30/35 15/21+30/49