Add 70/21 and 21/63, Solve 3 7/21 + 21/63 as a fraction

Add 70/21 and 21/63

1^st number: 3 7/21, 2^nd number: 21/63

70/21 + 21/63 is 11/3.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
70/21 = 70 × 3/21 × 3 = 210/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63
Add the two like fractions:
210/63 + 21/63 = 210 + 21/63 = 231/63
231/63 simplified gives 11/3
So, 70/21 + 21/63 = 11/3
In mixed form: 32/3

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