Subtract 8/18 from 25/21, Solve 1 4/21

Subtract 8/18 from 25/21

1^st number: 1 4/21, 2^nd number: 8/18

25/21 - 8/18 is 47/63.

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,
8/18 = 8 × 7/18 × 7 = 56/126
Subtract the two like fractions:
150/126 - 56/126 = 150 - 56/126 = 94/126
After reducing the fraction, the answer is 47/63

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