Working with directed number and negative numbers RESEARCH Explain how you would help someone to understand what can be said to be different between a temperature of minus 3°C (-3°C) and the number negative 3 ( -3 ). Is zero a positive or a negative number? SKILL 1. Evaluate the following without using a calculator a) -6 + - 9 b) 2 + - 7 c) 5 - - 8 d) -5 × 12 e) -8 - - 4 f) -72 ÷ 9 g) 8 × -3. 5 h) -6 ÷ 8 i) -7 – +26 j) -7 × -3 k) (-4) 2 2. a) The temperature is 4˚C. It rises by 5˚C. What is the new temperature? b) The temperature is -2˚C. It rises by 6˚C. What is the new temperature? c) The temperature was 12˚C and is now -3˚C. What is difference between these two temperatures? 3. At 6 am, the temperature in Eastbourne was -2°C. By 2 pm it had risen by 19°C. What was the temperature in Eastbourne now? 4. If it is -26°C in Canada and 34°C in Australia, what is the difference in temperature? 5. How much debt would I be in if I spent £ 235 but only have £ 128 in the bank? MEMORY When you go down. When you go up. add a positive number, you go up. subtract a positive number, you add a negative number, you go subtract a negative number, you CHALLENGE Mrs Forster thinks of 2 numbers. The product of these two numbers is -28. What COULD the two numbers possibly be? List the possibilities. The same two numbers have a sum of 3. What MUST the two numbers be?