Subtract 21/63 from 42/5, Solve 8 2/5

Subtract 21/63 from 42/5

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

42/5 - 21/63 is 121/15.

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
Subtract the two like fractions:
2646/315 - 105/315 = 2646 - 105/315 = 2541/315
After reducing the fraction, the answer is 121/15
In mixed form: 81/15

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