Subtract 42/10 from 30/40
1st number: 30/40, 2nd number: 4 2/10
30/40 - 42/10 is -69/20.
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,
30/40 = 30 × 1/40 × 1 = 30/40 - Likewise, for the 2nd fraction, since 10 × 4 = 40,
42/10 = 42 × 4/10 × 4 = 168/40 - Subtract the two like fractions:
30/40 - 168/40 = 30 - 168/40 = -138/40 - After reducing the fraction, the answer is -69/20
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