Subtract 21/45 from 40/20
1st number: 2 0/20, 2nd number: 21/45
40/20 - 21/45 is 23/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
40/20 = 40 × 9/20 × 9 = 360/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180 - Subtract the two like fractions:
360/180 - 84/180 = 360 - 84/180 = 276/180 - After reducing the fraction, the answer is 23/15
- In mixed form: 18/15
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