The graph shows the model of Water usage time t on x axis and Water used in gallons

w on Y axis .
What can be concluded from the point ( t , w ) is ( 6 , 30 ) on the graph?

A. The water usage is increasing at a rate of 5 gallons per minute .
B The water usage is increasing at a rate of per minute.
C The water usage increases from 1 gallon to 2 gallons in 1 minute.
D The Water usage increases from 1 gallon to 5 gallons in 5 minutes.

1 answer

To analyze the point (t, w) = (6, 30) on the graph, we need to determine what this point indicates regarding water usage over time.

The point (6, 30) means that at 6 minutes (t = 6), 30 gallons of water have been used (w = 30).

From here, we can derive the average rate of water usage:

  1. If at t = 0 (the start time, which we can assume is 0 unless otherwise stated) the water usage was 0 gallons, then at t = 6 minutes, the usage is 30 gallons.

  2. The rate of water usage can then be calculated as:

    \[ \text{Rate} = \frac{\text{Change in water used}}{\text{Change in time}} = \frac{30 \text{ gallons} - 0 \text{ gallons}}{6 \text{ minutes} - 0 \text{ minutes}} = \frac{30}{6} = 5 \text{ gallons per minute} \]

Now, we can evaluate the options provided:

A. The water usage is increasing at a rate of 5 gallons per minute. (This statement is correct based on the calculated rate.)

B. The water usage is increasing at a rate of per minute. (This statement is incomplete and thus cannot be evaluated as accurate.)

C. The water usage increases from 1 gallon to 2 gallons in 1 minute. (This statement is not supported by the information; the average rate is higher.)

D. The water usage increases from 1 gallon to 5 gallons in 5 minutes. (This statement is also not supported by the average rate calculation.)

Based on the analysis, the conclusion from the point (6, 30) on the graph is:

A. The water usage is increasing at a rate of 5 gallons per minute.