Subtract 9/70 from 18/20, Solve 18/20

Subtract 9/70 from 18/20

18/20 - 9/70 is 27/35.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 20 × 7 = 140,
18/20 = 18 × 7/20 × 7 = 126/140
Likewise, for the 2nd fraction, since 70 × 2 = 140,
9/70 = 9 × 2/70 × 2 = 18/140
Subtract the two like fractions:
126/140 - 18/140 = 126 - 18/140 = 108/140
After reducing the fraction, the answer is 27/35

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