**8**

- Work backwards. So 192/3 = 64
- 64 square root = 8

Use BIDMAS

**a) 2**

Solve what you can. So 23 x ? = 46. Then re-arrange the formula. ? = 46/23 = 2

**b) 4**

Remember BIDMAS. Solve 5-2 first = 3. So 3 to power of 2 is 3×3 = 9.

13 = ? + 9. Re-arrange to give 4

**c) 9**

2 + 6 = 8

72 ÷ ? = 8. Re-arrange to give 9

Completed blanks in the following order

81-25=56

14×4=56

They are the same. (NOTE: This is a nice trick to remember). Follow the example guideline.

(552+448)x(552-448) = 1000 x 104 = 104,000

(8.5+7.5)x(8.5-7.5) = 16 x 1 = 16

(19/37+18/37)x(19/37-18/37) = 37/37 x 1/37 = 1/37

(25001+24999)x(25001-24999) = 50,000 x 2 = 100,000

NOTE: The above is a great approach to remember for future questions.