Add 72/28 and 15/90
1st number: 2 16/28, 2nd number: 15/90
72/28 + 15/90 is 115/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
72/28 = 72 × 45/28 × 45 = 3240/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
15/90 = 15 × 14/90 × 14 = 210/1260 - Add the two like fractions:
3240/1260 + 210/1260 = 3240 + 210/1260 = 3450/1260 - 3450/1260 simplified gives 115/42
- So, 72/28 + 15/90 = 115/42
In mixed form: 231/42
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