Subtract 21/20 from 90/10
1st number: 9 0/10, 2nd number: 1 1/20
90/10 - 21/20 is 159/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 10 × 2 = 20,
90/10 = 90 × 2/10 × 2 = 180/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Subtract the two like fractions:
180/20 - 21/20 = 180 - 21/20 = 159/20 - In mixed form: 719/20
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