Subtract 90/45 from 40/21
1st number: 1 19/21, 2nd number: 2 0/45
40/21 - 90/45 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
40/21 = 40 × 15/21 × 15 = 600/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
90/45 = 90 × 7/45 × 7 = 630/315 - Subtract the two like fractions:
600/315 - 630/315 = 600 - 630/315 = -30/315 - After reducing the fraction, the answer is -2/21
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