Subtract 24/21 from 8/90, Solve 8/90

Subtract 24/21 from 8/90

1^st number: 8/90, 2^nd number: 1 3/21

8/90 - 24/21 is -332/315.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
8/90 = 8 × 7/90 × 7 = 56/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
24/21 = 24 × 30/21 × 30 = 720/630
Subtract the two like fractions:
56/630 - 720/630 = 56 - 720/630 = -664/630
After reducing the fraction, the answer is -332/315

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