Subtract 20/40 from 3/45
3/45 - 20/40 is -13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
3/45 = 3 × 8/45 × 8 = 24/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Subtract the two like fractions:
24/360 - 180/360 = 24 - 180/360 = -156/360 - After reducing the fraction, the answer is -13/30
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