Subtract 21/25 from 30/40
30/40 - 21/25 is -9/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 25 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 40 × 5 = 200,
30/40 = 30 × 5/40 × 5 = 150/200 - Likewise, for the 2nd fraction, since 25 × 8 = 200,
21/25 = 21 × 8/25 × 8 = 168/200 - Subtract the two like fractions:
150/200 - 168/200 = 150 - 168/200 = -18/200 - After reducing the fraction, the answer is -9/100
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