Subtract 90/27 from 40/21
1st number: 1 19/21, 2nd number: 3 9/27
40/21 - 90/27 is -10/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
40/21 = 40 × 9/21 × 9 = 360/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
90/27 = 90 × 7/27 × 7 = 630/189 - Subtract the two like fractions:
360/189 - 630/189 = 360 - 630/189 = -270/189 - After reducing the fraction, the answer is -10/7
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