Subtract 40/8 from 30/42
1st number: 30/42, 2nd number: 5 0/8
30/42 - 40/8 is -30/7.
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,
30/42 = 30 × 4/42 × 4 = 120/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
40/8 = 40 × 21/8 × 21 = 840/168 - Subtract the two like fractions:
120/168 - 840/168 = 120 - 840/168 = -720/168 - After reducing the fraction, the answer is -30/7
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