Add 21/16 and 72/70, Solve 1 5/16 + 1 2/70 as a fraction

Add 21/16 and 72/70

1^st number: 1 5/16, 2^nd number: 1 2/70

21/16 + 72/70 is 1311/560.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 70 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 16 × 35 = 560,
21/16 = 21 × 35/16 × 35 = 735/560
Likewise, for the 2nd fraction, since 70 × 8 = 560,
72/70 = 72 × 8/70 × 8 = 576/560
Add the two like fractions:
735/560 + 576/560 = 735 + 576/560 = 1311/560
So, 21/16 + 72/70 = 1311/560
In mixed form: 2191/560

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