Add 56/15 and 21/42, Solve 3 11/15 + 21/42 as a fraction

Add 56/15 and 21/42

1^st number: 3 11/15, 2^nd number: 21/42

56/15 + 21/42 is 127/30.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
56/15 = 56 × 14/15 × 14 = 784/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
784/210 + 105/210 = 784 + 105/210 = 889/210
889/210 simplified gives 127/30
So, 56/15 + 21/42 = 127/30
In mixed form: 47/30

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