Add 21/42 and 12/56
21/42 + 12/56 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
12/56 = 12 × 3/56 × 3 = 36/168 - Add the two like fractions:
84/168 + 36/168 = 84 + 36/168 = 120/168 - 120/168 simplified gives 5/7
- So, 21/42 + 12/56 = 5/7
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