Subtract 12/21 from 5/30, Solve 5/30

Subtract 12/21 from 5/30

5/30 - 12/21 is -17/42.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
5/30 = 5 × 7/30 × 7 = 35/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210
Subtract the two like fractions:
35/210 - 120/210 = 35 - 120/210 = -85/210
After reducing the fraction, the answer is -17/42

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