Add 15/42 and 90/28, Solve 15/42 + 3 6/28 as a fraction

Add 15/42 and 90/28

1^st number: 15/42, 2^nd number: 3 6/28

15/42 + 90/28 is 25/7.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 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 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84
Add the two like fractions:
30/84 + 270/84 = 30 + 270/84 = 300/84
300/84 simplified gives 25/7
So, 15/42 + 90/28 = 25/7
In mixed form: 34/7

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