Subtract 42/10 from 21/4
1st number: 5 1/4, 2nd number: 4 2/10
21/4 - 42/10 is 21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 10 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
21/4 = 21 × 5/4 × 5 = 105/20 - Likewise, for the 2nd fraction, since 10 × 2 = 20,
42/10 = 42 × 2/10 × 2 = 84/20 - Subtract the two like fractions:
105/20 - 84/20 = 105 - 84/20 = 21/20 - In mixed form: 11/20
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