Subtract 42/40 from 21/8
1st number: 2 5/8, 2nd number: 1 2/40
21/8 - 42/40 is 63/40.
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,
42/40 = 42 × 1/40 × 1 = 42/40 - Subtract the two like fractions:
105/40 - 42/40 = 105 - 42/40 = 63/40 - In mixed form: 123/40
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