Subtract 5/18 from 21/40
21/40 - 5/18 is 89/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
5/18 = 5 × 20/18 × 20 = 100/360 - Subtract the two like fractions:
189/360 - 100/360 = 189 - 100/360 = 89/360
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