Add 21/63 and 15/70
21/63 + 15/70 is 23/42.
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,
15/70 = 15 × 9/70 × 9 = 135/630 - Add the two like fractions:
210/630 + 135/630 = 210 + 135/630 = 345/630 - 345/630 simplified gives 23/42
- So, 21/63 + 15/70 = 23/42
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