Changed Applied-Algebra Exam Questions

This question asks us to read and interpret a value from a graph.

The horizontal axis represents:

" Days since the beginning of the month "

The vertical axis represents:

" Practice duration in minutes "

We need to find the practice duration for:

" day " 9

To do this, locate 9on the horizontal axis, move upward to the blue graph, and then read the corresponding value on the vertical axis.

From the graph, the point at day 9is approximately:

127

So the musician practiced for:

127 " minutes "

The graph represents the value of an investment account over time. The horizontal axis gives time in years, and the vertical axis gives the total account value in dollars. To find the value after 4 years, locate x=4 on the horizontal axis and read the corresponding G(x)-value on the graph. The plotted exponential growth curve is slightly above $1,000 at 4 years, closest to $1,052.87. Because the graph shows an increasing exponential trend, values such as $480.52, $584.62, and $711.28 are too low for the account value at x=4. The correct interpretation is that after 4 years, the investment account is worth approximately $1,052.87. Therefore, the correct answer is D.

This question is about reading an ordered pair from a graph.

An ordered pair has the form:

(x│y)

where:

x= " time in hours "

and

y= " audience size "

From the graph:

Point Ais at approximately (0│402)

Point Bis at (2│401)

Point Cis at (4│403)

Point Dis at (6│406)

Point Eis at approximately (8│410)

Point Fis at (10│408)

Now compare these graph points with the answer choices.

Choice A says:

(2│401)

This matches point Bon the graph exactly.

The other choices do not match the graph:

(4│404)

is incorrect because at x=4, the graph shows about 403, not 404.

(8│409)

is incorrect because at x=8, the graph is about 410, not 409.

(10│407)

is incorrect because at x=10, the graph shows about 408, not 407.

In this function-notation problem, the input represents last year’s number of people and the output represents this year’s expected number. Because this year’s number is 7 more than last year’s, the rule is A(t)=t+7. The question says 440 people auditioned last year, so the correct input is 440. Substituting gives A(440)=440+7=447. This means if 440 people auditioned last year, then 447 are expected to audition this year. The notation must place 440 inside the parentheses because that is the input value, and 447 must be written as the output value. The other options reverse the input and output or subtract instead of adding. Therefore, option C is correct.

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