Add 18/21 and 42/56
18/21 + 42/56 is 45/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
42/56 = 42 × 3/56 × 3 = 126/168 - Add the two like fractions:
144/168 + 126/168 = 144 + 126/168 = 270/168 - 270/168 simplified gives 45/28
- So, 18/21 + 42/56 = 45/28
In mixed form: 117/28
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