Add 15/21 and 28/49
15/21 + 28/49 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
15/21 = 15 × 7/21 × 7 = 105/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
28/49 = 28 × 3/49 × 3 = 84/147 - Add the two like fractions:
105/147 + 84/147 = 105 + 84/147 = 189/147 - 189/147 simplified gives 9/7
- So, 15/21 + 28/49 = 9/7
In mixed form: 12/7
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