Subtract 40/42 from 15/30
15/30 - 40/42 is -19/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210 - Subtract the two like fractions:
105/210 - 200/210 = 105 - 200/210 = -95/210 - After reducing the fraction, the answer is -19/42
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