Subtract 21/20 from 42/5
1st number: 8 2/5, 2nd number: 1 1/20
42/5 - 21/20 is 147/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 5 × 4 = 20,
42/5 = 42 × 4/5 × 4 = 168/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Subtract the two like fractions:
168/20 - 21/20 = 168 - 21/20 = 147/20 - In mixed form: 77/20
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