Subtract 21/36 from 90/20
1st number: 4 10/20, 2nd number: 21/36
90/20 - 21/36 is 47/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
90/20 = 90 × 9/20 × 9 = 810/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Subtract the two like fractions:
810/180 - 105/180 = 810 - 105/180 = 705/180 - After reducing the fraction, the answer is 47/12
- In mixed form: 311/12
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