Subtract 9/21 from 40/56
40/56 - 9/21 is 2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
40/56 = 40 × 3/56 × 3 = 120/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
9/21 = 9 × 8/21 × 8 = 72/168 - Subtract the two like fractions:
120/168 - 72/168 = 120 - 72/168 = 48/168 - After reducing the fraction, the answer is 2/7
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