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

Add 21/16 and 21/70

1^st number: 1 5/16, 2^nd number: 21/70

21/16 + 21/70 is 129/80.

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,
21/70 = 21 × 8/70 × 8 = 168/560
Add the two like fractions:
735/560 + 168/560 = 735 + 168/560 = 903/560
903/560 simplified gives 129/80
So, 21/16 + 21/70 = 129/80
In mixed form: 149/80

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