Subtract 18/20 from 42/10, Solve 4 2/10

Subtract 18/20 from 42/10

1^st number: 4 2/10, 2^nd number: 18/20

42/10 - 18/20 is 33/10.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 20 is 20

Next, find the equivalent fraction of both fractional numbers with denominator 20
For the 1st fraction, since 10 × 2 = 20,
42/10 = 42 × 2/10 × 2 = 84/20
Likewise, for the 2nd fraction, since 20 × 1 = 20,
18/20 = 18 × 1/20 × 1 = 18/20
Subtract the two like fractions:
84/20 - 18/20 = 84 - 18/20 = 66/20
After reducing the fraction, the answer is 33/10
In mixed form: 33/10

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