Add 70/12 and 21/42, Solve 5 10/12 + 21/42 as a fraction

Add 70/12 and 21/42

1^st number: 5 10/12, 2^nd number: 21/42

70/12 + 21/42 is 19/3.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
70/12 = 70 × 7/12 × 7 = 490/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84
Add the two like fractions:
490/84 + 42/84 = 490 + 42/84 = 532/84
532/84 simplified gives 19/3
So, 70/12 + 21/42 = 19/3
In mixed form: 61/3

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