Subtract 9/21 from 18/60, Solve 18/60

Subtract 9/21 from 18/60

18/60 - 9/21 is -9/70.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
18/60 = 18 × 7/60 × 7 = 126/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
9/21 = 9 × 20/21 × 20 = 180/420
Subtract the two like fractions:
126/420 - 180/420 = 126 - 180/420 = -54/420
After reducing the fraction, the answer is -9/70

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