Add 21/54 and 70/63, Solve 21/54 + 1 7/63 as a fraction

Add 21/54 and 70/63

1^st number: 21/54, 2^nd number: 1 7/63

21/54 + 70/63 is 3/2.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 63 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378
Likewise, for the 2nd fraction, since 63 × 6 = 378,
70/63 = 70 × 6/63 × 6 = 420/378
Add the two like fractions:
147/378 + 420/378 = 147 + 420/378 = 567/378
567/378 simplified gives 3/2
So, 21/54 + 70/63 = 3/2
In mixed form: 11/2

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