Answers

Subtract 20/90 from 42/64

42/64 - 20/90 is 125/288.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 64 and 90 is 2880
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2880
2. For the 1st fraction, since 64 × 45 = 2880,
   42/64 = 42 × 45/64 × 45 = 1890/2880
3. Likewise, for the 2nd fraction, since 90 × 32 = 2880,
   20/90 = 20 × 32/90 × 32 = 640/2880
4. Subtract the two like fractions:
   1890/2880 - 640/2880 = 1890 - 640/2880 = 1250/2880
5. After reducing the fraction, the answer is 125/288

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