Add 21/42 and 28/63
21/42 + 28/63 is 17/18.
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,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
28/63 = 28 × 2/63 × 2 = 56/126 - Add the two like fractions:
63/126 + 56/126 = 63 + 56/126 = 119/126 - 119/126 simplified gives 17/18
- So, 21/42 + 28/63 = 17/18
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