The suspended copper levels y (in parts per billion) in Silver Bow Creek are bel

Question

The suspended copper levels y (in parts per billion) in Silver Bow Creek are believed to increase quadratically with the flow rate x of Silver Bow Creek (in cubic feet per

second), according to the following model:

y = 4 + 0.2x + 0.015x2 + e.

a) What is the mean level of suspended copper in Silver Bow Creek when the creek is flowing at a rate of 600 cubic feet per second?

b) How much would the mean value of y increase when the value of x increases from 600 cubic feet per second to 700 cubic feet per second?

Explanation / Answer

Answer to paart a)

Y = 4 + 0.2 x + 0.015x2 + e

given : x = 600 cubic feet per second

Y = 4 + 0.2*600 + 0.015 * 600^2

Y = 5524

.

Answer to part b)

Y1 is the value of Y , for x1 = 600

y2 = is the value of Y, for x2 = 700

.

Now from part a , we know that y1 = 5524

.

For y2, we do the following calculations

y2 = 4 + 0.2 *700 + 0.015*700^2

y2 = 7494

.

Thus the increase in Y = y2 - y1

increase in Y = 7494 - 5524

increase in Y = 1970

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.