Answers

Subtract 21/72 from 70/20

1^st number: 3 10/20, 2^nd number: 21/72

70/20 - 21/72 is 77/24.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 20 × 18 = 360,
   70/20 = 70 × 18/20 × 18 = 1260/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   21/72 = 21 × 5/72 × 5 = 105/360
4. Subtract the two like fractions:
   1260/360 - 105/360 = 1260 - 105/360 = 1155/360
5. After reducing the fraction, the answer is 77/24
6. In mixed form: 35/24

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