Add 63/72 and 21/42
63/72 + 21/42 is 11/8.
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,
63/72 = 63 × 7/72 × 7 = 441/504 - Likewise, for the 2nd fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504 - Add the two like fractions:
441/504 + 252/504 = 441 + 252/504 = 693/504 - 693/504 simplified gives 11/8
- So, 63/72 + 21/42 = 11/8
In mixed form: 13/8
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