Add 42/63 and 20/21
42/63 + 20/21 is 34/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
42/63 = 42 × 1/63 × 1 = 42/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
20/21 = 20 × 3/21 × 3 = 60/63 - Add the two like fractions:
42/63 + 60/63 = 42 + 60/63 = 102/63 - 102/63 simplified gives 34/21
- So, 42/63 + 20/21 = 34/21
In mixed form: 113/21
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