Subtract 21/90 from 18/40
18/40 - 21/90 is 13/60.
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,
18/40 = 18 × 9/40 × 9 = 162/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Subtract the two like fractions:
162/360 - 84/360 = 162 - 84/360 = 78/360 - After reducing the fraction, the answer is 13/60
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