Subtract 81/45 from 40/42
1st number: 40/42, 2nd number: 1 36/45
40/42 - 81/45 is -89/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
81/45 = 81 × 14/45 × 14 = 1134/630 - Subtract the two like fractions:
600/630 - 1134/630 = 600 - 1134/630 = -534/630 - After reducing the fraction, the answer is -89/105
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