Subtract 20/40 from 42/5
1st number: 8 2/5, 2nd number: 20/40
42/5 - 20/40 is 79/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
42/5 = 42 × 8/5 × 8 = 336/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
20/40 = 20 × 1/40 × 1 = 20/40 - Subtract the two like fractions:
336/40 - 20/40 = 336 - 20/40 = 316/40 - After reducing the fraction, the answer is 79/10
- In mixed form: 79/10
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