Subtract 5/10 from 9/21, Solve 9/21

Subtract 5/10 from 9/21

9/21 - 5/10 is -1/14.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
9/21 = 9 × 10/21 × 10 = 90/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
5/10 = 5 × 21/10 × 21 = 105/210
Subtract the two like fractions:
90/210 - 105/210 = 90 - 105/210 = -15/210
After reducing the fraction, the answer is -1/14

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