Add 4/21 and 20/84
4/21 + 20/84 is 3/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
4/21 = 4 × 4/21 × 4 = 16/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
20/84 = 20 × 1/84 × 1 = 20/84 - Add the two like fractions:
16/84 + 20/84 = 16 + 20/84 = 36/84 - 36/84 simplified gives 3/7
- So, 4/21 + 20/84 = 3/7
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