Subtract 40/70 from 40/90
40/90 - 40/70 is -8/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 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 70 × 9 = 630,
40/70 = 40 × 9/70 × 9 = 360/630 - Subtract the two like fractions:
280/630 - 360/630 = 280 - 360/630 = -80/630 - After reducing the fraction, the answer is -8/63
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