Subtract 45/40 from 70/90
1st number: 70/90, 2nd number: 1 5/40
70/90 - 45/40 is -25/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
70/90 = 70 × 4/90 × 4 = 280/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
45/40 = 45 × 9/40 × 9 = 405/360 - Subtract the two like fractions:
280/360 - 405/360 = 280 - 405/360 = -125/360 - After reducing the fraction, the answer is -25/72
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