Subtract 40/8 from 3/21
1st number: 3/21, 2nd number: 5 0/8
3/21 - 40/8 is -34/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
3/21 = 3 × 8/21 × 8 = 24/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
40/8 = 40 × 21/8 × 21 = 840/168 - Subtract the two like fractions:
24/168 - 840/168 = 24 - 840/168 = -816/168 - After reducing the fraction, the answer is -34/7
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