Subtract 15/45 from 30/42, Solve 30/42

Subtract 15/45 from 30/42

30/42 - 15/45 is 8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
30/42 = 30 × 15/42 × 15 = 450/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630
Subtract the two like fractions:
450/630 - 210/630 = 450 - 210/630 = 240/630
After reducing the fraction, the answer is 8/21

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