Subtract 21/4 from 21/40
1st number: 21/40, 2nd number: 5 1/4
21/40 - 21/4 is -189/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 4 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 4 × 10 = 40,
21/4 = 21 × 10/4 × 10 = 210/40 - Subtract the two like fractions:
21/40 - 210/40 = 21 - 210/40 = -189/40
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