Add 10/30 and 21/40
10/30 + 21/40 is 103/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
10/30 = 10 × 4/30 × 4 = 40/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
40/120 + 63/120 = 40 + 63/120 = 103/120 - So, 10/30 + 21/40 = 103/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/30+21/40 10/30+42/40 10/60+21/40 10/30+21/80 10/30+63/40 10/90+21/40 50/30+21/40 70/30+21/40