Subtract 25/90 from 30/42, Solve 30/42

Subtract 25/90 from 30/42

30/42 - 25/90 is 55/126.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 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 90 × 7 = 630,
25/90 = 25 × 7/90 × 7 = 175/630
Subtract the two like fractions:
450/630 - 175/630 = 450 - 175/630 = 275/630
After reducing the fraction, the answer is 55/126

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