Add 21/84 and 3/20
21/84 + 3/20 is 2/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Add the two like fractions:
105/420 + 63/420 = 105 + 63/420 = 168/420 - 168/420 simplified gives 2/5
- So, 21/84 + 3/20 = 2/5
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