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## Negative Numbers

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -

**Negative Numbers**-5 -4 -3 -2 -1 0 1 2 3 4 5 counting negatively counting positively Any number above zero is a positive number. Positive numbers are written with no sign or a + sign in front of them and they are counted from zero to the right.**-5**-4 -3 -2 -1 0 1 2 3 4 5 counting negatively counting positively Any number below zero is a negative number. Negative numbers are written with a - sign in front of them and they are counted from zero to the left. Always look at the sign in front of a number to see if it is positive or negative.**-5**-4 -3 -2 -1 0 1 2 3 4 5 counting negatively counting positively Remember: Positive numbers get bigger the further we move right, so 5 is bigger than 2. Negative numbers get smaller the further we move left, so -5 is smaller than -2.**-5**-4 -3 -2 -1 0 1 2 3 4 5 counting negatively counting positively Example: Which word, “bigger” or “smaller”, would fit correctly In each of these gaps? smaller -7 is ___________than -1 +62 is ___________than -71 -136 is ___________than -36 bigger smaller**Why do negative numbers "get bigger"?**As you extend a number line showing negative numbers,they seem to get “bigger.” -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2**-10**-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 The numbers seem to increase in value as they go down the number line. But as the negative number gets bigger, the value gets lower. -10 is a larger number than -5, so it is further below zero. If you look at the number line you can see that -10 is less than -5.**a**d m s w e -4 -2 0 2 4 Let's Practice -10 8 What value is letter w? What value is letter a? Which value is bigger -10 or 8? Even though 10 is a bigger number than 8, 8 is bigger because 10 is negative.**o**Spring 7 C o o Fall -4 C Winter -12 C If it helps you remember, think about the weather. As temperature gets lower the negative numbers seem to get bigger.**Temperature increase and decrease**When the weather changes the temperature can go up or down. If a temperature goes up, gets warmer, it is a temperature increase. If a temperature goes down, gets colder, it is a temperature decrease.**During the summer when you wake up, the morning**temperature could be 3 C. By lunchtime it is up to 10 C. o o This is a temperature increase of 7 C. 15 15 10 10 5 5 o 0 0 -5 -5 Example:**In the early afternoon the temperature is 15 C. By early**evening the temperature goes down to 12 C. o o 15 This is a temperature decrease of 3 C. 15 10 10 5 5 0 o 0 -5 -5**During winter the early morning temperature could**be -3 C. By lunch it is up to 6 C. o o o o o From -3 C to 0 C is 3 C. 15 15 10 10 This is a temperature increase of 9 C. 5 5 o 0 0 -5 -5 o o o From 0 C to 6 C is a further 6 C. o o The total of 3 C + 6 C makes 9 C. o But what happens if we have negative temperatures? Example:**In the early afternoon the temperature is 3 C. By early**evening the temperature goes down to -5 C. o o 15 o o o From 3 C to 0 C is 3 C. 15 10 10 5 0 5 0 -5 This is a temperature decrease of 8 C. -5 o o o o The total of 3 C + 5 C makes 8 C. o o o From 0 C to -5 C is a further 5 C.**14**10 o 2 C 6 o C Let's Practice What temperature is shown on the thermometer?**35**25 o -5 C 10 0 o C What temperature is shown on the thermometer?