Add 20/72 and 9/42
20/72 + 9/42 is 31/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 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 42 × 12 = 504,
9/42 = 9 × 12/42 × 12 = 108/504 - Add the two like fractions:
140/504 + 108/504 = 140 + 108/504 = 248/504 - 248/504 simplified gives 31/63
- So, 20/72 + 9/42 = 31/63
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