Add 21/72 and 15/63
21/72 + 15/63 is 89/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
15/63 = 15 × 8/63 × 8 = 120/504 - Add the two like fractions:
147/504 + 120/504 = 147 + 120/504 = 267/504 - 267/504 simplified gives 89/168
- So, 21/72 + 15/63 = 89/168
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