Add 21/70 and 18/12, Solve 21/70 + 1 6/12 as a fraction

Add 21/70 and 18/12

1^st number: 21/70, 2^nd number: 1 6/12

21/70 + 18/12 is 9/5.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420
Likewise, for the 2nd fraction, since 12 × 35 = 420,
18/12 = 18 × 35/12 × 35 = 630/420
Add the two like fractions:
126/420 + 630/420 = 126 + 630/420 = 756/420
756/420 simplified gives 9/5
So, 21/70 + 18/12 = 9/5
In mixed form: 14/5

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