Answers

Subtract 21/80 from 70/90

70/90 - 21/80 is 371/720.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 90 × 8 = 720,
   70/90 = 70 × 8/90 × 8 = 560/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   21/80 = 21 × 9/80 × 9 = 189/720
4. Subtract the two like fractions:
   560/720 - 189/720 = 560 - 189/720 = 371/720

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