Subtract 40/8 from 7/21
1st number: 7/21, 2nd number: 5 0/8
7/21 - 40/8 is -14/3.
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,
7/21 = 7 × 8/21 × 8 = 56/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
40/8 = 40 × 21/8 × 21 = 840/168 - Subtract the two like fractions:
56/168 - 840/168 = 56 - 840/168 = -784/168 - After reducing the fraction, the answer is -14/3
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