Question

The swimming pool is open when the high temperature is higher than 20^\circ\text{C}20 ? C20, degree, C. Lainey tried to swim on Monday and Thursday (which was 333 days later). The pool was open on Monday, but it was closed on Thursday. The high temperature was 30^\circ\text{C}30 ? C30, degree, C on Monday, but decreased at a constant rate in the next 333 days.

Answer 1

Answer:

$30-3d\leq 20$

Step by step explanation:

Let d represent the rate of temperature decrease in degrees Celsius per day from Monday to Thursday.  

As temperature decreased at a constant rate in the next 3 days, so the rate of temperature will decrease 3d degree Celsius in 3 days.  

We are told that the pool was open on Monday. The high temperature was $30^{\circ}{\text{C}$ on Monday. So the decrease in temperature from Monday to Thursday will be $30-3d$.

We have been given that the swimming pool is open when the high temperature is higher than $20^{\circ}{\text{C}$.

As the pool was closed on Thursday. This means that temperature on Thursday was less than or equal to 20 degree Celsius. We can represent this information in an inequality as:

$30-3d\leq 20$

Therefore, the inequality $30-3d\leq 20$ can be used to determine the rate of temperature decrease in degrees Celsius per day, d, from Monday to Thursday.