Subtract 21/40 from 45/75
45/75 - 21/40 is 3/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 40 is 600
Next, find the equivalent fraction of both fractional numbers with denominator 600 - For the 1st fraction, since 75 × 8 = 600,
45/75 = 45 × 8/75 × 8 = 360/600 - Likewise, for the 2nd fraction, since 40 × 15 = 600,
21/40 = 21 × 15/40 × 15 = 315/600 - Subtract the two like fractions:
360/600 - 315/600 = 360 - 315/600 = 45/600 - After reducing the fraction, the answer is 3/40
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