Add 18/42 and 21/56
18/42 + 21/56 is 45/56.
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,
18/42 = 18 × 4/42 × 4 = 72/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Add the two like fractions:
72/168 + 63/168 = 72 + 63/168 = 135/168 - 135/168 simplified gives 45/56
- So, 18/42 + 21/56 = 45/56
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