Add 21/15 and 70/28
1st number: 1 6/15, 2nd number: 2 14/28
21/15 + 70/28 is 39/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
70/28 = 70 × 15/28 × 15 = 1050/420 - Add the two like fractions:
588/420 + 1050/420 = 588 + 1050/420 = 1638/420 - 1638/420 simplified gives 39/10
- So, 21/15 + 70/28 = 39/10
In mixed form: 39/10
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