Subtract 30/40 from 21/8
1st number: 2 5/8, 2nd number: 30/40
21/8 - 30/40 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
30/40 = 30 × 1/40 × 1 = 30/40 - Subtract the two like fractions:
105/40 - 30/40 = 105 - 30/40 = 75/40 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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