Add 72/42 and 28/21
1st number: 1 30/42, 2nd number: 1 7/21
72/42 + 28/21 is 64/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
72/42 = 72 × 1/42 × 1 = 72/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
28/21 = 28 × 2/21 × 2 = 56/42 - Add the two like fractions:
72/42 + 56/42 = 72 + 56/42 = 128/42 - 128/42 simplified gives 64/21
- So, 72/42 + 28/21 = 64/21
In mixed form: 31/21
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