Answers

Subtract 40/21 from 35/72

1^st number: 35/72, 2^nd number: 1 19/21

35/72 - 40/21 is -715/504.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 21 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 72 × 7 = 504,
   35/72 = 35 × 7/72 × 7 = 245/504
3. Likewise, for the 2nd fraction, since 21 × 24 = 504,
   40/21 = 40 × 24/21 × 24 = 960/504
4. Subtract the two like fractions:
   245/504 - 960/504 = 245 - 960/504 = -715/504

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