Subtract 21/40 from 42/8
1st number: 5 2/8, 2nd number: 21/40
42/8 - 21/40 is 189/40.
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,
42/8 = 42 × 5/8 × 5 = 210/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Subtract the two like fractions:
210/40 - 21/40 = 210 - 21/40 = 189/40 - In mixed form: 429/40
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