Subtract 42/63 from 40/90
40/90 - 42/63 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
40/90 = 40 × 7/90 × 7 = 280/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
42/63 = 42 × 10/63 × 10 = 420/630 - Subtract the two like fractions:
280/630 - 420/630 = 280 - 420/630 = -140/630 - After reducing the fraction, the answer is -2/9
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