Add 4/21 and 70/12, Solve 4/21 + 5 10/12 as a fraction

Add 4/21 and 70/12

1^st number: 4/21, 2^nd number: 5 10/12

4/21 + 70/12 is 253/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
4/21 = 4 × 4/21 × 4 = 16/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
70/12 = 70 × 7/12 × 7 = 490/84
Add the two like fractions:
16/84 + 490/84 = 16 + 490/84 = 506/84
506/84 simplified gives 253/42
So, 4/21 + 70/12 = 253/42
In mixed form: 61/42

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