Add 20/21 and 30/72
20/21 + 30/72 is 115/84.
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,
20/21 = 20 × 24/21 × 24 = 480/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504 - Add the two like fractions:
480/504 + 210/504 = 480 + 210/504 = 690/504 - 690/504 simplified gives 115/84
- So, 20/21 + 30/72 = 115/84
In mixed form: 131/84
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