Subtract 21/20 from 72/9
1st number: 8 0/9, 2nd number: 1 1/20
72/9 - 21/20 is 139/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
72/9 = 72 × 20/9 × 20 = 1440/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
1440/180 - 189/180 = 1440 - 189/180 = 1251/180 - After reducing the fraction, the answer is 139/20
- In mixed form: 619/20
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