Add 72/84 and 1/21
72/84 + 1/21 is 19/21.
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,
1/21 = 1 × 4/21 × 4 = 4/84 - Add the two like fractions:
72/84 + 4/84 = 72 + 4/84 = 76/84 - 76/84 simplified gives 19/21
- So, 72/84 + 1/21 = 19/21
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