Subtract 5/90 from 21/40
21/40 - 5/90 is 169/360.
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,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
5/90 = 5 × 4/90 × 4 = 20/360 - Subtract the two like fractions:
189/360 - 20/360 = 189 - 20/360 = 169/360
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