Subtract 40/8 from 12/42
1st number: 12/42, 2nd number: 5 0/8
12/42 - 40/8 is -33/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
12/42 = 12 × 4/42 × 4 = 48/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
40/8 = 40 × 21/8 × 21 = 840/168 - Subtract the two like fractions:
48/168 - 840/168 = 48 - 840/168 = -792/168 - After reducing the fraction, the answer is -33/7
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