Subtract 20/5 from 9/42, Solve 9/42

Subtract 20/5 from 9/42

1^st number: 9/42, 2^nd number: 4 0/5

9/42 - 20/5 is -53/14.

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,
9/42 = 9 × 5/42 × 5 = 45/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
20/5 = 20 × 42/5 × 42 = 840/210
Subtract the two like fractions:
45/210 - 840/210 = 45 - 840/210 = -795/210
After reducing the fraction, the answer is -53/14

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