Subtract 15/90 from 21/5
1st number: 4 1/5, 2nd number: 15/90
21/5 - 15/90 is 121/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
15/90 = 15 × 1/90 × 1 = 15/90 - Subtract the two like fractions:
378/90 - 15/90 = 378 - 15/90 = 363/90 - After reducing the fraction, the answer is 121/30
- In mixed form: 41/30
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