Subtract 21/8 from 40/42
1st number: 40/42, 2nd number: 2 5/8
40/42 - 21/8 is -281/168.
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,
40/42 = 40 × 4/42 × 4 = 160/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
160/168 - 441/168 = 160 - 441/168 = -281/168
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