6. A ball starts at a height of 21 metres. It then falls at a constant rate of 3 metres per second.
(i) After how many seconds will the ball hit the ground? (ii) Draw a graph to show this information. (iii) Identify the variables in this question.
7. A bus is carrying 24 people. At each stop, 4 people get off the bus. No one gets on the bus. (i) How many stops must the bus make so all the passengers have gotten off? (ii) Draw a graph to show this information. (iii) At which stop will the bus contain 8 passengers?
8. Mary and John each get a bank account. Mary starts by putting €10 into her account and then adds €2 per week. John doesn’t put anything into his account at the start, but saves €4 into it every week.
(i) Create a table showing Mary’s savings and a table showing John’s savings over the first 7 weeks. (ii) Draw a graph showing the amount that Mary has in her account each week for the first 7 weeks.
(iii) Using the same axes and scale, draw a graph showing the amount that John has in his account each week, for the first 7 weeks.
(iv) During which week will the amounts in their accounts be equal?
9. Two identical containers are being filled with water. Each container is 30 cm tall. Container A is empty at the start of the experiment. Once the experiment starts, the water level rises by 3 cm per minute.
A
Container B already contains water at a height of 5 cm before the experiment begins. Once the experiment starts, the water level rises by 2 cm per minute.
(i) Create a table showing how the water levels in each container change over 5 minutes.
(ii) Draw a graph showing the height of the water in container A over 10 minutes.
(iii) Using the same axes and scale, draw a graph showing the height of the water in container B over 10 minutes.
(iv) Will the containers ever contain exactly the same level of water? Justify your answer.
B
7⋅3 Examining the rate of change of a pattern
There are many different types of pattern, but for now, we will be looking at patterns that have the
By the end of this section you should:
● understand what the slope (rate of change) of a graph is
● be able to calculate the slope of a straight line graph
● understand how the rate of change in a pattern/ graph is linked to its slope
same rate of change in each stage. These are called linear patterns.
A linear pattern exists if the points that make it up form a straight line. A linear pattern has the same difference between stages.