Subtract 3/90 from 21/25, Solve 21/25

Subtract 3/90 from 21/25

21/25 - 3/90 is 121/150.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 90 is 450

Next, find the equivalent fraction of both fractional numbers with denominator 450
For the 1st fraction, since 25 × 18 = 450,
21/25 = 21 × 18/25 × 18 = 378/450
Likewise, for the 2nd fraction, since 90 × 5 = 450,
3/90 = 3 × 5/90 × 5 = 15/450
Subtract the two like fractions:
378/450 - 15/450 = 378 - 15/450 = 363/450
After reducing the fraction, the answer is 121/150

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