Add 28/42 and 20/72
28/42 + 20/72 is 17/18.
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,
28/42 = 28 × 12/42 × 12 = 336/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Add the two like fractions:
336/504 + 140/504 = 336 + 140/504 = 476/504 - 476/504 simplified gives 17/18
- So, 28/42 + 20/72 = 17/18
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