Subtract 40/15 from 30/42
1st number: 30/42, 2nd number: 2 10/15
30/42 - 40/15 is -41/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
40/15 = 40 × 14/15 × 14 = 560/210 - Subtract the two like fractions:
150/210 - 560/210 = 150 - 560/210 = -410/210 - After reducing the fraction, the answer is -41/21
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