Add 15/21 and 70/6, Solve 15/21 + 11 4/6 as a fraction

Add 15/21 and 70/6

1^st number: 15/21, 2^nd number: 11 4/6

15/21 + 70/6 is 260/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42
Likewise, for the 2nd fraction, since 6 × 7 = 42,
70/6 = 70 × 7/6 × 7 = 490/42
Add the two like fractions:
30/42 + 490/42 = 30 + 490/42 = 520/42
520/42 simplified gives 260/21
So, 15/21 + 70/6 = 260/21
In mixed form: 128/21

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