Add 15/42 and 28/21
1st number: 15/42, 2nd number: 1 7/21
15/42 + 28/21 is 71/42.
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,
15/42 = 15 × 1/42 × 1 = 15/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
28/21 = 28 × 2/21 × 2 = 56/42 - Add the two like fractions:
15/42 + 56/42 = 15 + 56/42 = 71/42 - So, 15/42 + 28/21 = 71/42
In mixed form: 129/42
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