Subtract 20/18 from 25/21, Solve 1 4/21

Subtract 20/18 from 25/21

1^st number: 1 4/21, 2^nd number: 1 2/18

25/21 - 20/18 is 5/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
25/21 = 25 × 6/21 × 6 = 150/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126
Subtract the two like fractions:
150/126 - 140/126 = 150 - 140/126 = 10/126
After reducing the fraction, the answer is 5/63

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