Add 12/42 and 21/63
12/42 + 21/63 is 13/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
12/42 = 12 × 3/42 × 3 = 36/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
21/63 = 21 × 2/63 × 2 = 42/126 - Add the two like fractions:
36/126 + 42/126 = 36 + 42/126 = 78/126 - 78/126 simplified gives 13/21
- So, 12/42 + 21/63 = 13/21
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