Subtract 42/16 from 21/40
1st number: 21/40, 2nd number: 2 10/16
21/40 - 42/16 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
42/16 = 42 × 5/16 × 5 = 210/80 - Subtract the two like fractions:
42/80 - 210/80 = 42 - 210/80 = -168/80 - After reducing the fraction, the answer is -21/10
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