Add 72/84 and 4/21
72/84 + 4/21 is 22/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
72/84 = 72 × 1/84 × 1 = 72/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
4/21 = 4 × 4/21 × 4 = 16/84 - Add the two like fractions:
72/84 + 16/84 = 72 + 16/84 = 88/84 - 88/84 simplified gives 22/21
- So, 72/84 + 4/21 = 22/21
In mixed form: 11/21
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