Add 5/21 and 30/72
5/21 + 30/72 is 55/84.
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,
5/21 = 5 × 24/21 × 24 = 120/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504 - Add the two like fractions:
120/504 + 210/504 = 120 + 210/504 = 330/504 - 330/504 simplified gives 55/84
- So, 5/21 + 30/72 = 55/84
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