Question

An ecologist studied the lengths, %0D%0An%0D%0A%0D%0A inches, and weights, %0D%0Aw%0D%0A%0D%0A pounds, of a group of sunfish. Her results are recorded in the graph below.%0D%0A%0D%0A%0D%0A%0D%0ABased on the data, which of the following values best approximates the weight, in pounds, of a sunfish with a length of 18 inches?%0D%0A%0D%0A%09A.%09%0D%0A2.3%0D%0A%0D%0A%09B.%09%0D%0A3.1%0D%0A%0D%0A%09C.%09%0D%0A3.9%0D%0A%0D%0A%09D.%09%0D%0A4.7%0D%0A%0D%0A%09E.%09%0D%0A15.9

Answer 1

To find the weight of a sunfish with a length of 18 inches, we can look at the graph and see that the weight increases linearly as the length increases.

From the data given in the graph, we can calculate the slope of the line by finding the change in weight divided by the change in length.

Using the data provided in the graph:
For a length of 15 inches, the weight is approximately 2.3 pounds.
For a length of 21 inches, the weight is approximately 4.7 pounds.

Therefore, the slope of the line is:
(4.7 - 2.3) / (21 - 15) = 2.4 / 6 = 0.4

Now, we can use the slope to estimate the weight of a sunfish with a length of 18 inches:
Weight = 2.3 + 0.4 * (18 - 15) = 2.3 + 0.4 * 3 = 2.3 + 1.2 = 3.5

So, the best approximation for the weight of a sunfish with a length of 18 inches is 3.5 pounds.

Therefore, the closest answer choice is:
B. 3.1