Answers

Subtract 64/9 from 21/8

1^st number: 2 5/8, 2^nd number: 7 1/9

21/8 - 64/9 is -323/72.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 8 and 9 is 72
   
   Next, find the equivalent fraction of both fractional numbers with denominator 72
2. For the 1st fraction, since 8 × 9 = 72,
   21/8 = 21 × 9/8 × 9 = 189/72
3. Likewise, for the 2nd fraction, since 9 × 8 = 72,
   64/9 = 64 × 8/9 × 8 = 512/72
4. Subtract the two like fractions:
   189/72 - 512/72 = 189 - 512/72 = -323/72

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