Answers

Subtract 8/90 from 7/21

7/21 - 8/90 is 11/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 21 × 30 = 630,
   7/21 = 7 × 30/21 × 30 = 210/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   8/90 = 8 × 7/90 × 7 = 56/630
4. Subtract the two like fractions:
   210/630 - 56/630 = 210 - 56/630 = 154/630
5. After reducing the fraction, the answer is 11/45

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