Add 21/30 and 18/63
21/30 + 18/63 is 69/70.
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,
18/63 = 18 × 10/63 × 10 = 180/630 - Add the two like fractions:
441/630 + 180/630 = 441 + 180/630 = 621/630 - 621/630 simplified gives 69/70
- So, 21/30 + 18/63 = 69/70
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