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-5 -4 -3 -2 -1 counting negatively 0 1 2 3 4 5 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 counting negatively 0 1 2 3 4 5 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 counting negatively 0 1 2 3 4 5 counting positively 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 counting negatively 0 1 2 3 4 5 counting positively Which word, “bigger” or “smaller”, would fit correctly In each of these gaps? smaller -7 is ___________than -1 bigger +62 is ___________than -71 smaller -136 is ___________than -36 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 -10 m s -4 -2 0 2 4 w e 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. If it helps you remember, think about the weather. As temperature gets lower the negative numbers seem to get bigger. o Spring 7 C o Fall -4 C o Winter -12 C 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 o temperature could be 3 C. By lunchtime it is up o to 10 C. 15 15 10 10 5 5 0 0 -5 -5 This is a temperature increase of o 7 C. o In the early afternoon the temperature is 15 C. By early o evening the temperature goes down to 12 C. 15 15 10 10 5 5 0 0 -5 -5 This is a temperature decrease of o 3 C. But what happens if we have negative temperatures? Example: During winter the early morning temperature could o o be -3 C. By lunch it is up to 6 C. o 15 o 15 10 From 0 C to 6 C is a further 6 C. o 10 o From -3 C to 0 C is 3 C. o o o 5 5 0 0 -5 -5 o The total of 3oC + 6 C makes 9 C. This is a temperature o increase of 9 C. o In the early afternoon the temperature is 3 C. By early o evening the temperature goes down to -5 C. 15 10 5 15 10 5 0 0 -5 -5 o o o From 3 C to 0 C is 3 C. o o o From 0 C to -5 C is a further 5 C. o o o The total of 3 C + 5 C makes 8 C. This is a temperature o decrease of 8 C. 14 What temperature is shown on the thermometer? 10 o 2C 6 C o 35 What temperature is shown on the thermometer? 25 10 o -5 C 0 C o