Add 7/21 and 21/72
7/21 + 21/72 is 5/8.
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,
7/21 = 7 × 24/21 × 24 = 168/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
168/504 + 147/504 = 168 + 147/504 = 315/504 - 315/504 simplified gives 5/8
- So, 7/21 + 21/72 = 5/8
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