Add 12/15 and 21/63
12/15 + 21/63 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 63 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 15 × 21 = 315,
12/15 = 12 × 21/15 × 21 = 252/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Add the two like fractions:
252/315 + 105/315 = 252 + 105/315 = 357/315 - 357/315 simplified gives 17/15
- So, 12/15 + 21/63 = 17/15
In mixed form: 12/15
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