Answer:
a) The function that represents the amount of water as a function of time is
f(x) = 30,000 - 400x
b) The amount of water left in the sink after half an hour of starting to empty it
= 18,000 litres
c) The time it will take to empty the sink completely = 75 minutes.
Explanation:
English Translation
A sink is emptied with a pump that extracts water at the rate of 400 liters per minute. when turning on the pump in the sink there were 30000 liters of water.
a) The time (in minutes) from when the pump is turned on is called x. find the function that represents the amount of water left in the sink as a function of time
b) Determine the amount of water left in the sink after half an hour of starting to empty it.
c) Determine the time it will take to empty the sink completely?
a) Speed is a quantity that is described as the rate of change of another quantity with time.
So, the speed of emptying the sink is given as
Speed = (Amount of water emptied) ÷ (Time taken to empty that amount of water).
The Speed of emptying the sink is given as 400 litres/min
Time taken to empty the sink = x
Let the amount of water left in the sink, a function of the time taken to empty the sink, be f(x)
Amount of water emptied = 30,000 - f(x)
400 = [30000 - f(x)] ÷ x
30000 - f(x) = 400x
f(x) = 30,000 - 400x
b) Determine the amount of water left in the sink after half an hour of starting to empty it.
f(x) = 30000 - 400x
x = 30 mins
f(x) = 30000 - 400(30) = 18,000 litres
c) Determine the time it will take to empty the sink completely?
f(x) = 30000 - 400x
when the sink is completely empty, the amount of water left in the sink is 0 litres, that is, f(x) = 0 litres
0 = 30000 - 400x
400x = 30000
x = (30000/400) = 75 minutes.
Hope this Helps!!!