Add 21/30 and 72/63
1st number: 21/30, 2nd number: 1 9/63
21/30 + 72/63 is 129/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 30 × 21 = 630,
21/30 = 21 × 21/30 × 21 = 441/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
72/63 = 72 × 10/63 × 10 = 720/630 - Add the two like fractions:
441/630 + 720/630 = 441 + 720/630 = 1161/630 - 1161/630 simplified gives 129/70
- So, 21/30 + 72/63 = 129/70
In mixed form: 159/70
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