Add 15/4 and 15/42, Solve 3 3/4 + 15/42 as a fraction

Add 15/4 and 15/42

1^st number: 3 3/4, 2^nd number: 15/42

15/4 + 15/42 is 115/28.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
15/4 = 15 × 21/4 × 21 = 315/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
15/42 = 15 × 2/42 × 2 = 30/84
Add the two like fractions:
315/84 + 30/84 = 315 + 30/84 = 345/84
345/84 simplified gives 115/28
So, 15/4 + 15/42 = 115/28
In mixed form: 43/28

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