Subtract 21/90 from 12/40
12/40 - 21/90 is 1/15.
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,
12/40 = 12 × 9/40 × 9 = 108/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Subtract the two like fractions:
108/360 - 84/360 = 108 - 84/360 = 24/360 - After reducing the fraction, the answer is 1/15
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