Subtract 21/20 from 42/8
1st number: 5 2/8, 2nd number: 1 1/20
42/8 - 21/20 is 21/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 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 20 × 2 = 40,
21/20 = 21 × 2/20 × 2 = 42/40 - Subtract the two like fractions:
210/40 - 42/40 = 210 - 42/40 = 168/40 - After reducing the fraction, the answer is 21/5
- In mixed form: 41/5
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