Subtract 21/63 from 30/8, Solve 3 6/8

Subtract 21/63 from 30/8

1^st number: 3 6/8, 2^nd number: 21/63

30/8 - 21/63 is 41/12.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 63 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 8 × 63 = 504,
30/8 = 30 × 63/8 × 63 = 1890/504
Likewise, for the 2nd fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504
Subtract the two like fractions:
1890/504 - 168/504 = 1890 - 168/504 = 1722/504
After reducing the fraction, the answer is 41/12
In mixed form: 35/12

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