Add 15/42 and 18/4, Solve 15/42 + 4 2/4 as a fraction

Add 15/42 and 18/4

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

15/42 + 18/4 is 34/7.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
15/42 = 15 × 2/42 × 2 = 30/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84
Add the two like fractions:
30/84 + 378/84 = 30 + 378/84 = 408/84
408/84 simplified gives 34/7
So, 15/42 + 18/4 = 34/7
In mixed form: 46/7

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