Add 8/21 and 42/72
8/21 + 42/72 is 27/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
8/21 = 8 × 24/21 × 24 = 192/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
42/72 = 42 × 7/72 × 7 = 294/504 - Add the two like fractions:
192/504 + 294/504 = 192 + 294/504 = 486/504 - 486/504 simplified gives 27/28
- So, 8/21 + 42/72 = 27/28
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