Add 15/72 and 21/42
15/72 + 21/42 is 17/24.
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,
15/72 = 15 × 7/72 × 7 = 105/504 - Likewise, for the 2nd fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504 - Add the two like fractions:
105/504 + 252/504 = 105 + 252/504 = 357/504 - 357/504 simplified gives 17/24
- So, 15/72 + 21/42 = 17/24
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