Subtract 21/5 from 20/40
1st number: 20/40, 2nd number: 4 1/5
20/40 - 21/5 is -37/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 5 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
20/40 = 20 × 1/40 × 1 = 20/40 - Likewise, for the 2nd fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Subtract the two like fractions:
20/40 - 168/40 = 20 - 168/40 = -148/40 - After reducing the fraction, the answer is -37/10
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