Add 72/15 and 21/42
1st number: 4 12/15, 2nd number: 21/42
72/15 + 21/42 is 53/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
72/15 = 72 × 14/15 × 14 = 1008/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Add the two like fractions:
1008/210 + 105/210 = 1008 + 105/210 = 1113/210 - 1113/210 simplified gives 53/10
- So, 72/15 + 21/42 = 53/10
In mixed form: 53/10
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