Add 70/21 and 20/54, Solve 3 7/21 + 20/54 as a fraction

Add 70/21 and 20/54

1^st number: 3 7/21, 2^nd number: 20/54

70/21 + 20/54 is 100/27.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
70/21 = 70 × 18/21 × 18 = 1260/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378
Add the two like fractions:
1260/378 + 140/378 = 1260 + 140/378 = 1400/378
1400/378 simplified gives 100/27
So, 70/21 + 20/54 = 100/27
In mixed form: 319/27

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