Add 7/20 and 6/21
7/20 + 6/21 is 89/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
6/21 = 6 × 20/21 × 20 = 120/420 - Add the two like fractions:
147/420 + 120/420 = 147 + 120/420 = 267/420 - 267/420 simplified gives 89/140
- So, 7/20 + 6/21 = 89/140
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