Add 5/12 and 70/21, Solve 5/12 + 3 7/21 as a fraction

Add 5/12 and 70/21

1^st number: 5/12, 2^nd number: 3 7/21

5/12 + 70/21 is 15/4.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
5/12 = 5 × 7/12 × 7 = 35/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84
Add the two like fractions:
35/84 + 280/84 = 35 + 280/84 = 315/84
315/84 simplified gives 15/4
So, 5/12 + 70/21 = 15/4
In mixed form: 33/4

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