Subtract 40/42 from 3/15
3/15 - 40/42 is -79/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
3/15 = 3 × 14/15 × 14 = 42/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210 - Subtract the two like fractions:
42/210 - 200/210 = 42 - 200/210 = -158/210 - After reducing the fraction, the answer is -79/105
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