Subtract 3/15 from 81/63, Solve 1 18/63

Subtract 3/15 from 81/63

1^st number: 1 18/63, 2^nd number: 3/15

81/63 - 3/15 is 38/35.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 15 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 63 × 5 = 315,
81/63 = 81 × 5/63 × 5 = 405/315
Likewise, for the 2nd fraction, since 15 × 21 = 315,
3/15 = 3 × 21/15 × 21 = 63/315
Subtract the two like fractions:
405/315 - 63/315 = 405 - 63/315 = 342/315
After reducing the fraction, the answer is 38/35
In mixed form: 13/35

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