Add 21/63 and 42/70
21/63 + 42/70 is 14/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
42/70 = 42 × 9/70 × 9 = 378/630 - Add the two like fractions:
210/630 + 378/630 = 210 + 378/630 = 588/630 - 588/630 simplified gives 14/15
- So, 21/63 + 42/70 = 14/15
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