Subtract 18/10 from 40/42
1st number: 40/42, 2nd number: 1 8/10
40/42 - 18/10 is -89/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Subtract the two like fractions:
200/210 - 378/210 = 200 - 378/210 = -178/210 - After reducing the fraction, the answer is -89/105
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