Add 7/42 and 20/72
7/42 + 20/72 is 4/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
7/42 = 7 × 12/42 × 12 = 84/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
84/504 + 140/504 = 84 + 140/504 = 224/504 - 224/504 simplified gives 4/9
- So, 7/42 + 20/72 = 4/9
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