sat suite question viewer
A ball is dropped from an initial height of feet and bounces off the ground repeatedly. The function estimates that the maximum height reached after each time the ball hits the ground is of the maximum height reached after the previous time the ball hit the ground. Which equation defines , where is the estimated maximum height of the ball after it has hit the ground times and is a whole number greater than and less than ?
Explanation
Choice B is correct. It's given that for the function , is the estimated maximum height, in feet, of the ball after it has hit the ground times. It's also given that the function estimates that the maximum height reached after each time the ball hits the ground is of the maximum height reached after the previous time the ball hit the ground. It follows that is a decreasing exponential function that can be written in the form , where is the initial height, in feet, the ball was dropped from and the function estimates that the maximum height reached after each time the ball hits the ground is of the maximum height reached after the previous time the ball hit the ground. It's given that the ball is dropped from an initial height of feet. Therefore, . Since the function estimates that the maximum height reached after each time the ball hits the ground is of the maximum height reached after the previous time the ball hit the ground, . Substituting for and for in the equation yields , or .
Choice A is incorrect. This function estimates that the maximum height reached after each time the ball hits the ground is , not , of the maximum height reached after the previous time the ball hit the ground.
Choice C is incorrect. This function estimates that the ball is dropped from an initial height of feet, not feet, and that the maximum height reached after each time the ball hits the ground is , not , of the maximum height reached after the previous time the ball hit the ground.
Choice D is incorrect. This function estimates that the ball is dropped from an initial height of feet, not feet.