Subtract 30/9 from 10/20, Solve 10/20

Subtract 30/9 from 10/20

1^st number: 10/20, 2^nd number: 3 3/9

10/20 - 30/9 is -17/6.

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

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 20 × 9 = 180,
10/20 = 10 × 9/20 × 9 = 90/180
Likewise, for the 2nd fraction, since 9 × 20 = 180,
30/9 = 30 × 20/9 × 20 = 600/180
Subtract the two like fractions:
90/180 - 600/180 = 90 - 600/180 = -510/180
After reducing the fraction, the answer is -17/6

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