Subtract 1/90 from 21/15
1st number: 1 6/15, 2nd number: 1/90
21/15 - 1/90 is 25/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
1/90 = 1 × 1/90 × 1 = 1/90 - Subtract the two like fractions:
126/90 - 1/90 = 126 - 1/90 = 125/90 - After reducing the fraction, the answer is 25/18
- In mixed form: 17/18
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