Subtract 18/45 from 21/5
1st number: 4 1/5, 2nd number: 18/45
21/5 - 18/45 is 19/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 45 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 5 × 9 = 45,
21/5 = 21 × 9/5 × 9 = 189/45 - Likewise, for the 2nd fraction, since 45 × 1 = 45,
18/45 = 18 × 1/45 × 1 = 18/45 - Subtract the two like fractions:
189/45 - 18/45 = 189 - 18/45 = 171/45 - After reducing the fraction, the answer is 19/5
- In mixed form: 34/5
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