Subtract 45/70 from 10/21, Solve 10/21

Subtract 45/70 from 10/21

10/21 - 45/70 is -1/6.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
45/70 = 45 × 3/70 × 3 = 135/210
Subtract the two like fractions:
100/210 - 135/210 = 100 - 135/210 = -35/210
After reducing the fraction, the answer is -1/6

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