Subtract 21/10 from 42/8
1st number: 5 2/8, 2nd number: 2 1/10
42/8 - 21/10 is 63/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 10 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 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Subtract the two like fractions:
210/40 - 84/40 = 210 - 84/40 = 126/40 - After reducing the fraction, the answer is 63/20
- In mixed form: 33/20
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