Interactive practice questions
In a study, scientists found that the more someone sleeps, the quicker their reaction time. The attached table shows the findings. Use a positive number to express increase, and a negative number to express decrease.
| Number of hours of sleep ($x$x) | $0$0 | $1$1 | $2$2 | $3$3 | $4$4 | $5$5 |
|---|---|---|---|---|---|---|
| Reaction time in seconds ($y$y) | $6$6 | $5.8$5.8 | $5.6$5.6 | $5.4$5.4 | $5.2$5.2 | $5$5 |
How much does the reaction time change for each extra hour of sleep? Express your answer correct to one decimal place.
Which one of the following algebraic equations relates the number of hours of sleep ($x$x) and the reaction time ($y$y)?
$y=6x-0.2$y=6x−0.2
$y=-0.2x-6$y=−0.2x−6
$y=-0.2x+6$y=−0.2x+6
What would be the reaction time for someone who has slept $4.5$4.5 hours?
Express your answer correct to two decimal places.
By rearranging the equation found in part (b), calculate the number of hours, correct to one decimal place, someone sleeps if they have a reaction time of $5.5$5.5 seconds.
Enter each line of working as an equation.
The recommended level of good cholesterol in women, in mg/dL, can be modeled by the function $f\left(x\right)=0.13x+51.25$f(x)=0.13x+51.25, where $x$x is measured in years.
A ball is rolled down a slope. The table attached shows the velocity of the ball after a given number of seconds.
Consider the figure shown below.