Add 21/70 and 63/5, Solve 21/70 + 12 3/5 as a fraction

Add 21/70 and 63/5

1^st number: 21/70, 2^nd number: 12 3/5

21/70 + 63/5 is 129/10.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 5 is 70

Next, find the equivalent fraction of both fractional numbers with denominator 70
For the 1st fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70
Likewise, for the 2nd fraction, since 5 × 14 = 70,
63/5 = 63 × 14/5 × 14 = 882/70
Add the two like fractions:
21/70 + 882/70 = 21 + 882/70 = 903/70
903/70 simplified gives 129/10
So, 21/70 + 63/5 = 129/10
In mixed form: 129/10

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