Subtract 7/90 from 21/20
1st number: 1 1/20, 2nd number: 7/90
21/20 - 7/90 is 35/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
7/90 = 7 × 2/90 × 2 = 14/180 - Subtract the two like fractions:
189/180 - 14/180 = 189 - 14/180 = 175/180 - After reducing the fraction, the answer is 35/36
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