Add 20/72 and 42/63
20/72 + 42/63 is 17/18.
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,
20/72 = 20 × 7/72 × 7 = 140/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
42/63 = 42 × 8/63 × 8 = 336/504 - Add the two like fractions:
140/504 + 336/504 = 140 + 336/504 = 476/504 - 476/504 simplified gives 17/18
- So, 20/72 + 42/63 = 17/18
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