Add 42/5 and 21/63, Solve 8 2/5 + 21/63 as a fraction

Add 42/5 and 21/63

1^st number: 8 2/5, 2^nd number: 21/63

42/5 + 21/63 is 131/15.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 63 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 5 × 63 = 315,
42/5 = 42 × 63/5 × 63 = 2646/315
Likewise, for the 2nd fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315
Add the two like fractions:
2646/315 + 105/315 = 2646 + 105/315 = 2751/315
2751/315 simplified gives 131/15
So, 42/5 + 21/63 = 131/15
In mixed form: 811/15

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