Answers

Subtract 21/45 from 72/40

1^st number: 1 32/40, 2^nd number: 21/45

72/40 - 21/45 is 4/3.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 45 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 40 × 9 = 360,
   72/40 = 72 × 9/40 × 9 = 648/360
3. Likewise, for the 2nd fraction, since 45 × 8 = 360,
   21/45 = 21 × 8/45 × 8 = 168/360
4. Subtract the two like fractions:
   648/360 - 168/360 = 648 - 168/360 = 480/360
5. After reducing the fraction, the answer is 4/3
6. In mixed form: 11/3

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