1. Think of a number Multiply it by 2 Add 8 Divide by 2 Subtract the number you started with What is your answer? Mind reading

2. 4

3. Think of a number Add 3 Double it Subtract it again Subtract the number you first thought of What is your answer? Mind reading

4. 6

5. Everybody started with different numbers, but ended up with the same number. Why? The number you first thought of is always eventually subtracted. Everyone has performed the same operations so you all end up with the same answer. Mind reading

6. Think of a number n Mind reading

7. Multiply it by 3 3n3n Mind reading

8. Add 14 3n + 14 Mind reading

9. Subtract the number you first thought of 2n + 14 Mind reading

10. Divide by 2 n + 7 Mind reading

11. Subtract the number you first thought of 7 Mind reading

12. 3n is an expression. 3n + 8 is an expression with two terms. An expression consists of one or more terms. Expressions

13. Think of a Number Double it Add 3 Multiply by 4 Subtract 12 Divide by 8.

14. Think of a Number Double it Add 20 Subtract original number Subtract 5 Subtract original number.

15. Think of a Number Add 4 Subtract 3 Add 9 Subtract original number.

16. Think of a Number Add 8 Double it Subtract original number Subtract 1 Subtract original number.

17. Think of a Number Add 3 Double it Subtract original number Add 1 Subtract original number.

18. Think of a Number Add 2 Treble it Subtract original number Halve it Subtract original number Add 4.

19. Think of a number Double it Add 3 Multiply by 4 Subtract 12 Divide by 8 n 2n 2n+3 8n+12 8n n