Subtract 21/10 from 42/40
1st number: 1 2/40, 2nd number: 2 1/10
42/40 - 21/10 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 10 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
42/40 = 42 × 1/40 × 1 = 42/40 - Likewise, for the 2nd fraction, since 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Subtract the two like fractions:
42/40 - 84/40 = 42 - 84/40 = -42/40 - After reducing the fraction, the answer is -21/20
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