Add 42/56 and 21/15
1st number: 42/56, 2nd number: 1 6/15
42/56 + 21/15 is 43/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 15 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 56 × 15 = 840,
42/56 = 42 × 15/56 × 15 = 630/840 - Likewise, for the 2nd fraction, since 15 × 56 = 840,
21/15 = 21 × 56/15 × 56 = 1176/840 - Add the two like fractions:
630/840 + 1176/840 = 630 + 1176/840 = 1806/840 - 1806/840 simplified gives 43/20
- So, 42/56 + 21/15 = 43/20
In mixed form: 23/20
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