Subtract 18/40 from 21/5
1st number: 4 1/5, 2nd number: 18/40
21/5 - 18/40 is 15/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
18/40 = 18 × 1/40 × 1 = 18/40 - Subtract the two like fractions:
168/40 - 18/40 = 168 - 18/40 = 150/40 - After reducing the fraction, the answer is 15/4
- In mixed form: 33/4
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