Subtract 21/40 from 45/50
45/50 - 21/40 is 3/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 40 is 200
Next, find the equivalent fraction of both fractional numbers with denominator 200 - For the 1st fraction, since 50 × 4 = 200,
45/50 = 45 × 4/50 × 4 = 180/200 - Likewise, for the 2nd fraction, since 40 × 5 = 200,
21/40 = 21 × 5/40 × 5 = 105/200 - Subtract the two like fractions:
180/200 - 105/200 = 180 - 105/200 = 75/200 - After reducing the fraction, the answer is 3/8
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