Add 15/20 and 21/63
15/20 + 21/63 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 63 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 20 × 63 = 1260,
15/20 = 15 × 63/20 × 63 = 945/1260 - Likewise, for the 2nd fraction, since 63 × 20 = 1260,
21/63 = 21 × 20/63 × 20 = 420/1260 - Add the two like fractions:
945/1260 + 420/1260 = 945 + 420/1260 = 1365/1260 - 1365/1260 simplified gives 13/12
- So, 15/20 + 21/63 = 13/12
In mixed form: 11/12
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