Question

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Answer 1

$\sf\large\underline\blue{Given :}$

A = { 3,6,9,12,15,18,21 }, B = { 4,8,12,16,20 }, C = { 2,4,6,8,10,12,14,16 }, D = { 5,10,15,20 }

$\sf\large\underline\blue{According\:to\:the\:question\::}$

1. A - B

=> A = { 3,6,9,12,15,18,21 } - B = { 4,8,12,16,20 }

=> $\sf\large\underline\red{\:{3,6,9,15,18,21}\:}$

2. A - C

=> A = { 3,6,9,12,15,18,21 } - C = { 2,4,6,8,10,12,14,16 }

=> $\sf\large\underline\red{\:{3,9,15,18,21}\:}$

3. A - D

=> A = { 3,6,9,12,15,18,21 } - D = { 5,10,15,20 }

=> $\sf\large\underline\red{\:{3,6,9,12,18,21}\:}$

4. B - A

=> B = { 4,8,12,16,20 } - A = { 3,6,9,12,15,18,21 }

=> $\sf\large\underline\red{\:{4,8,16,20}\:}$

5. C - A

=> C = { 2,4,6,8,10,12,14,16 } - A = { 3,6,9,12,15,18,21 }

=> $\sf\large\underline\red{\:{2,4,8,10,14,16}\:}$

6. D - A

=> D = { 5,10,15,20 } - A = { 3,6,9,12,15,18,21 }

=> $\sf\large\underline\red{\:{5,10,20}\:}$

7. B - C

=> B = { 4,8,12,16,20 } - C = { 2,4,6,8,10,12,14,16 }

=> $\sf\large\underline\red{\:{20}\:}$

8. B - D

=> B = { 4,8,12,16,20 } - D = { 5,10,15,20 }

=> $\sf\large\underline\red{\:{4,8,12,16}\:}$

9. C - B

=> C = { 2,4,6,8,10,12,14,16 } - B = { 4,8,12,16,20 }

=> $\sf\large\underline\red{\:{2,6,10,14}\:}$

10. D - B

=> D = { 5,10,15,20 } - B = { 4,8,12,16,20 }

=> $\sf\large\underline\red{\:{5,10,15}\:}$

11. C - D

=> C = { 2,4,6,8,10,12,14,16 } - D = { 5,10,15,20 }

=> $\sf\large\underline\red{\:{2,4,6,8,12,14,16}\:}$

12. D - C

=> D = { 5,10,15,20 } - C = { 2,4,6,8,10,12,14,16 }

=> $\sf\large\underline\red{\:{5,15,20}\:}$