Subtract 7/90 from 3/40
3/40 - 7/90 is -1/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
3/40 = 3 × 9/40 × 9 = 27/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
7/90 = 7 × 4/90 × 4 = 28/360 - Subtract the two like fractions:
27/360 - 28/360 = 27 - 28/360 = -1/360
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