Add 21/30 and 45/63
21/30 + 45/63 is 99/70.
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,
45/63 = 45 × 10/63 × 10 = 450/630 - Add the two like fractions:
441/630 + 450/630 = 441 + 450/630 = 891/630 - 891/630 simplified gives 99/70
- So, 21/30 + 45/63 = 99/70
In mixed form: 129/70
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