Add 72/21 and 81/42
1st number: 3 9/21, 2nd number: 1 39/42
72/21 + 81/42 is 75/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Add the two like fractions:
144/42 + 81/42 = 144 + 81/42 = 225/42 - 225/42 simplified gives 75/14
- So, 72/21 + 81/42 = 75/14
In mixed form: 55/14
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