132 Other Examples Evaluate 20 + (30 - 10) + 5. Using order of operations: 20+ (30 - 10)+5+ Using a scientific calculator: Press: Compute Inside the parentheses first 30 10 5 20 + 20 + 20-5 Next, divide. 24 204 Finally, add. Display will read: 24 Evaluate 42-(4+6) + 2. Using a scientific calculator: Press: Using order of operations: 42 - (4 + 6) +2 Compute inside the parentheses first. 4 - 10+2 + Evaluate exponents. 2 4 + 1 16 -10 + 2 Then divide. Display will read: HI 16 - 5 Finally, subtract. 11 Explain it 1. To evaluate 3 (7 + 5), what should you do first and why? 2. In the second example using the scientific calculator, what is the purpose of the key? 6 Evaluate each expression. 9. 33 - 8x3 10. (52 + 7) + 4 11. 6 x 4-4+2 12. 18 - 3 x 5+2 13. 49 - 4x (49 + 7) 14. (64 + 8) 3+6 15. 72 +(4+4) 5 16. (3 x 3) x (2 x 2) + 36 Use parentheses to make each number sentence true. 17. 5+ 4 x 3 x 3 = 41 18. 9 x 0 + 4 = 36 19. 52 - 6x 0 = 25 21. 5+4 x 3 x 3 = 81 22. 9 x 0 + 4 - 4 20. 8 X 9 - 2 - 3 = 32 25. 1+2 x 3 + 4 = 21 23. 52 - 6x 0 - 0 24. 8 X 9 - 2 - 3 - 53 27. 5 X 6 X 8 - 7 = 30 28. 62+7+9 10 - 133 26. 2? + 4 x 6 = 48 isted in care