Subtract 20/5 from 40/42
1st number: 40/42, 2nd number: 4 0/5
40/42 - 20/5 is -64/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
40/42 = 40 × 5/42 × 5 = 200/210 - Likewise, for the 2nd fraction, since 5 × 42 = 210,
20/5 = 20 × 42/5 × 42 = 840/210 - Subtract the two like fractions:
200/210 - 840/210 = 200 - 840/210 = -640/210 - After reducing the fraction, the answer is -64/21
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