Subtract 40/45 from 42/90
42/90 - 40/45 is -19/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
40/45 = 40 × 2/45 × 2 = 80/90 - Subtract the two like fractions:
42/90 - 80/90 = 42 - 80/90 = -38/90 - After reducing the fraction, the answer is -19/45
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