Subtract 18/63 from 21/10, Solve 2 1/10

Subtract 18/63 from 21/10

1^st number: 2 1/10, 2^nd number: 18/63

21/10 - 18/63 is 127/70.

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,
21/10 = 21 × 63/10 × 63 = 1323/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
18/63 = 18 × 10/63 × 10 = 180/630
Subtract the two like fractions:
1323/630 - 180/630 = 1323 - 180/630 = 1143/630
After reducing the fraction, the answer is 127/70
In mixed form: 157/70

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