Add 4/21 and 70/18, Solve 4/21 + 3 16/18 as a fraction

Add 4/21 and 70/18

1^st number: 4/21, 2^nd number: 3 16/18

4/21 + 70/18 is 257/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
4/21 = 4 × 6/21 × 6 = 24/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126
Add the two like fractions:
24/126 + 490/126 = 24 + 490/126 = 514/126
514/126 simplified gives 257/63
So, 4/21 + 70/18 = 257/63
In mixed form: 45/63

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