Add 21/56 and 40/72
21/56 + 40/72 is 67/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 56 × 9 = 504,
21/56 = 21 × 9/56 × 9 = 189/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Add the two like fractions:
189/504 + 280/504 = 189 + 280/504 = 469/504 - 469/504 simplified gives 67/72
- So, 21/56 + 40/72 = 67/72
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