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

Subtract 30/42 from 42/45

42/45 - 30/42 is 23/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
42/45 = 42 × 14/45 × 14 = 588/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
30/42 = 30 × 15/42 × 15 = 450/630
Subtract the two like fractions:
588/630 - 450/630 = 588 - 450/630 = 138/630
After reducing the fraction, the answer is 23/105

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