Subtract 9/10 from 21/25
21/25 - 9/10 is -3/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 10 is 50
Next, find the equivalent fraction of both fractional numbers with denominator 50 - For the 1st fraction, since 25 × 2 = 50,
21/25 = 21 × 2/25 × 2 = 42/50 - Likewise, for the 2nd fraction, since 10 × 5 = 50,
9/10 = 9 × 5/10 × 5 = 45/50 - Subtract the two like fractions:
42/50 - 45/50 = 42 - 45/50 = -3/50
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