Add 72/15 and 21/30
1st number: 4 12/15, 2nd number: 21/30
72/15 + 21/30 is 11/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 15 × 2 = 30,
72/15 = 72 × 2/15 × 2 = 144/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Add the two like fractions:
144/30 + 21/30 = 144 + 21/30 = 165/30 - 165/30 simplified gives 11/2
- So, 72/15 + 21/30 = 11/2
In mixed form: 51/2
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