Subtract 42/10 from 21/40
1st number: 21/40, 2nd number: 4 2/10
21/40 - 42/10 is -147/40.
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,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 10 × 4 = 40,
42/10 = 42 × 4/10 × 4 = 168/40 - Subtract the two like fractions:
21/40 - 168/40 = 21 - 168/40 = -147/40
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