Add 5/20 and 7/21
5/20 + 7/21 is 7/12.
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,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420 - Add the two like fractions:
105/420 + 140/420 = 105 + 140/420 = 245/420 - 245/420 simplified gives 7/12
- So, 5/20 + 7/21 = 7/12
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