Add 21/15 and 28/63
1st number: 1 6/15, 2nd number: 28/63
21/15 + 28/63 is 83/45.
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,
21/15 = 21 × 21/15 × 21 = 441/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
28/63 = 28 × 5/63 × 5 = 140/315 - Add the two like fractions:
441/315 + 140/315 = 441 + 140/315 = 581/315 - 581/315 simplified gives 83/45
- So, 21/15 + 28/63 = 83/45
In mixed form: 138/45
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