Add 72/21 and 21/63
1st number: 3 9/21, 2nd number: 21/63
72/21 + 21/63 is 79/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63 - Add the two like fractions:
216/63 + 21/63 = 216 + 21/63 = 237/63 - 237/63 simplified gives 79/21
- So, 72/21 + 21/63 = 79/21
In mixed form: 316/21
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