Add 7/21 and 8/20
7/21 + 8/20 is 11/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Add the two like fractions:
140/420 + 168/420 = 140 + 168/420 = 308/420 - 308/420 simplified gives 11/15
- So, 7/21 + 8/20 = 11/15
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