Add 42/56 and 30/21
1st number: 42/56, 2nd number: 1 9/21
42/56 + 30/21 is 61/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
42/56 = 42 × 3/56 × 3 = 126/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
30/21 = 30 × 8/21 × 8 = 240/168 - Add the two like fractions:
126/168 + 240/168 = 126 + 240/168 = 366/168 - 366/168 simplified gives 61/28
- So, 42/56 + 30/21 = 61/28
In mixed form: 25/28
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