Add 21/42 and 20/84
21/42 + 20/84 is 31/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Add the two like fractions:
42/84 + 20/84 = 42 + 20/84 = 62/84 - 62/84 simplified gives 31/42
- So, 21/42 + 20/84 = 31/42
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