Add 21/42 and 1/30
21/42 + 1/30 is 8/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
1/30 = 1 × 7/30 × 7 = 7/210 - Add the two like fractions:
105/210 + 7/210 = 105 + 7/210 = 112/210 - 112/210 simplified gives 8/15
- So, 21/42 + 1/30 = 8/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42+2/30 21/84+1/30 21/42+1/60 63/42+1/30 21/42+3/30 21/42+1/90 21/42+5/30 21/42+7/30