Interactive practice questions
A diver starts at the surface of the water and begins to descend below the surface at a constant rate. The table shows the depth of the diver over $5$5 minutes.
| Number of minutes passed ($x$x) | $0$0 | $1$1 | $2$2 | $3$3 | $4$4 |
|---|---|---|---|---|---|
| Depth of diver in meters ($y$y) | $0$0 | $1.4$1.4 | $2.8$2.8 | $4.2$4.2 | $5.6$5.6 |
What is the increase in depth each minute?
Write an equation for the relationship between the number of minutes passed ($x$x) and the depth ($y$y) of the diver.
Enter each line of work as an equation.
In the equation, $y=1.4x$y=1.4x, what does $1.4$1.4 represent?
The change in depth per minute.
The diver’s depth below the surface.
The number of minutes passed.
At what depth would the diver be after $6$6 minutes?
We want to know how long the diver takes to reach $12.6$12.6 meters beneath the surface.
If we substitute $y=12.6$y=12.6 into the equation in part (b) we get $12.6=1.4x$12.6=1.4x.
Solve this equation for $x$x to find the time it takes.
The cost of a taxi ride $C$C is given by $C=5.5t+3$C=5.5t+3, where $t$t=duration of trip in minutes.
After Mae starts running, her heartbeat increases at a constant rate.
It starts raining and an empty rainwater tank fills up at a constant rate of $2$2 litres per hour. By midnight, there are $20$20 litres of water in a rainwater tank. As it rains, the tank continues to fill up at this rate.