Answers

Subtract 7/90 from 9/21

9/21 - 7/90 is 221/630.

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,
   9/21 = 9 × 30/21 × 30 = 270/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   7/90 = 7 × 7/90 × 7 = 49/630
4. Subtract the two like fractions:
   270/630 - 49/630 = 270 - 49/630 = 221/630

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