Subtract 42/20 from 4/9, Solve 4/9 - 2 2/20 as a fraction

Subtract 42/20 from 4/9

1^st number: 4/9, 2^nd number: 2 2/20

4/9 - 42/20 is -149/90.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 9 × 20 = 180,
4/9 = 4 × 20/9 × 20 = 80/180
Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180
Subtract the two like fractions:
80/180 - 378/180 = 80 - 378/180 = -298/180
After reducing the fraction, the answer is -149/90

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