Subtract 21/90 from 15/2
1st number: 7 1/2, 2nd number: 21/90
15/2 - 21/90 is 109/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
15/2 = 15 × 45/2 × 45 = 675/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
675/90 - 21/90 = 675 - 21/90 = 654/90 - After reducing the fraction, the answer is 109/15
- In mixed form: 74/15
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