Subtract 21/63 from 18/10, Solve 1 8/10

Subtract 21/63 from 18/10

1^st number: 1 8/10, 2^nd number: 21/63

18/10 - 21/63 is 22/15.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 10 × 63 = 630,
18/10 = 18 × 63/10 × 63 = 1134/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
21/63 = 21 × 10/63 × 10 = 210/630
Subtract the two like fractions:
1134/630 - 210/630 = 1134 - 210/630 = 924/630
After reducing the fraction, the answer is 22/15
In mixed form: 17/15

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