Add 42/63 and 20/70
42/63 + 20/70 is 20/21.
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,
42/63 = 42 × 10/63 × 10 = 420/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Add the two like fractions:
420/630 + 180/630 = 420 + 180/630 = 600/630 - 600/630 simplified gives 20/21
- So, 42/63 + 20/70 = 20/21
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