Subtract 21/63 from 45/30, Solve 1 15/30

Subtract 21/63 from 45/30

1^st number: 1 15/30, 2^nd number: 21/63

45/30 - 21/63 is 7/6.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 30 × 21 = 630,
45/30 = 45 × 21/30 × 21 = 945/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630
Subtract the two like fractions:
945/630 - 210/630 = 945 - 210/630 = 735/630
After reducing the fraction, the answer is 7/6
In mixed form: 11/6

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