Add 8/42 and 7/21
8/42 + 7/21 is 11/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
8/42 = 8 × 1/42 × 1 = 8/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
7/21 = 7 × 2/21 × 2 = 14/42 - Add the two like fractions:
8/42 + 14/42 = 8 + 14/42 = 22/42 - 22/42 simplified gives 11/21
- So, 8/42 + 7/21 = 11/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/42+7/21 8/42+14/21 8/84+7/21 8/42+7/42 24/42+7/21 8/42+7/63 40/42+7/21 8/42+35/21 56/42+7/21 8/42+49/21