Add 20/12 and 21/70, Solve 1 8/12 + 21/70 as a fraction

Add 20/12 and 21/70

1^st number: 1 8/12, 2^nd number: 21/70

20/12 + 21/70 is 59/30.

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,
20/12 = 20 × 35/12 × 35 = 700/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420
Add the two like fractions:
700/420 + 126/420 = 700 + 126/420 = 826/420
826/420 simplified gives 59/30
So, 20/12 + 21/70 = 59/30
In mixed form: 129/30

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