Subtract 25/40 from 10/21
10/21 - 25/40 is -25/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
10/21 = 10 × 40/21 × 40 = 400/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
25/40 = 25 × 21/40 × 21 = 525/840 - Subtract the two like fractions:
400/840 - 525/840 = 400 - 525/840 = -125/840 - After reducing the fraction, the answer is -25/168
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