Add 72/21 and 36/42
1st number: 3 9/21, 2nd number: 36/42
72/21 + 36/42 is 30/7.
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,
36/42 = 36 × 1/42 × 1 = 36/42 - Add the two like fractions:
144/42 + 36/42 = 144 + 36/42 = 180/42 - 180/42 simplified gives 30/7
- So, 72/21 + 36/42 = 30/7
In mixed form: 42/7
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