Subtract 18/21 from 5/10, Solve 5/10

Subtract 18/21 from 5/10

5/10 - 18/21 is -5/14.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
5/10 = 5 × 21/10 × 21 = 105/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210
Subtract the two like fractions:
105/210 - 180/210 = 105 - 180/210 = -75/210
After reducing the fraction, the answer is -5/14

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