Add 15/4 and 70/21, Solve 3 3/4 + 3 7/21 as a fraction

Add 15/4 and 70/21

1^st number: 3 3/4, 2^nd number: 3 7/21

15/4 + 70/21 is 85/12.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 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 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84
Add the two like fractions:
315/84 + 280/84 = 315 + 280/84 = 595/84
595/84 simplified gives 85/12
So, 15/4 + 70/21 = 85/12
In mixed form: 71/12

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