Add 21/12 and 16/70, Solve 1 9/12 + 16/70 as a fraction

Add 21/12 and 16/70

1^st number: 1 9/12, 2^nd number: 16/70

21/12 + 16/70 is 277/140.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
16/70 = 16 × 6/70 × 6 = 96/420
Add the two like fractions:
735/420 + 96/420 = 735 + 96/420 = 831/420
831/420 simplified gives 277/140
So, 21/12 + 16/70 = 277/140
In mixed form: 1137/140

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