Subtract 8/84 from 21/25, Solve 21/25

Subtract 8/84 from 21/25

21/25 - 8/84 is 391/525.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 84 is 2100

Next, find the equivalent fraction of both fractional numbers with denominator 2100
For the 1st fraction, since 25 × 84 = 2100,
21/25 = 21 × 84/25 × 84 = 1764/2100
Likewise, for the 2nd fraction, since 84 × 25 = 2100,
8/84 = 8 × 25/84 × 25 = 200/2100
Subtract the two like fractions:
1764/2100 - 200/2100 = 1764 - 200/2100 = 1564/2100
After reducing the fraction, the answer is 391/525

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