Subtract 21/8 from 42/5
1st number: 8 2/5, 2nd number: 2 5/8
42/5 - 21/8 is 231/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
42/5 = 42 × 8/5 × 8 = 336/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Subtract the two like fractions:
336/40 - 105/40 = 336 - 105/40 = 231/40 - In mixed form: 531/40
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