Add 3/5 and 21/42
3/5 + 21/42 is 11/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 5 × 42 = 210,
3/5 = 3 × 42/5 × 42 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Add the two like fractions:
126/210 + 105/210 = 126 + 105/210 = 231/210 - 231/210 simplified gives 11/10
- So, 3/5 + 21/42 = 11/10
In mixed form: 11/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/5+21/42 3/10+21/42 3/5+21/84 9/5+21/42 3/5+63/42 3/15+21/42 15/5+21/42 3/25+21/42 21/5+21/42 3/35+21/42