Add 21/70 and 84/72, Solve 21/70 + 1 12/72 as a fraction

Add 21/70 and 84/72

1^st number: 21/70, 2^nd number: 1 12/72

21/70 + 84/72 is 22/15.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 70 × 36 = 2520,
21/70 = 21 × 36/70 × 36 = 756/2520
Likewise, for the 2nd fraction, since 72 × 35 = 2520,
84/72 = 84 × 35/72 × 35 = 2940/2520
Add the two like fractions:
756/2520 + 2940/2520 = 756 + 2940/2520 = 3696/2520
3696/2520 simplified gives 22/15
So, 21/70 + 84/72 = 22/15
In mixed form: 17/15

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