Subtract 63/42 from 25/90, Solve 25/90

Subtract 63/42 from 25/90

1^st number: 25/90, 2^nd number: 1 21/42

25/90 - 63/42 is -11/9.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
25/90 = 25 × 7/90 × 7 = 175/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
63/42 = 63 × 15/42 × 15 = 945/630
Subtract the two like fractions:
175/630 - 945/630 = 175 - 945/630 = -770/630
After reducing the fraction, the answer is -11/9

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