Add 72/20 and 21/63
1st number: 3 12/20, 2nd number: 21/63
72/20 + 21/63 is 59/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 63 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 20 × 63 = 1260,
72/20 = 72 × 63/20 × 63 = 4536/1260 - Likewise, for the 2nd fraction, since 63 × 20 = 1260,
21/63 = 21 × 20/63 × 20 = 420/1260 - Add the two like fractions:
4536/1260 + 420/1260 = 4536 + 420/1260 = 4956/1260 - 4956/1260 simplified gives 59/15
- So, 72/20 + 21/63 = 59/15
In mixed form: 314/15
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