Keith modeled the growth over several hundred years of a tree population by estimating the number of the trees' pollen grains per square centimeter that were deposited each year within layers of a lake's sediment. He estimated there were 310 pollen grains per square centimeter the first year the grains were deposited, with a 1%  annual increase in the number of grains per square centimeter thereafter. Which of the following functions models p(t), the number of pollen grains per square centimeter t years after the first year the grains were deposited?

In the xy-plane, a line that has the equation y = c for some constant c intersects a parabola at exactly one point. If the parabola has the equation , what is the value of  c ?

The system of equations above is graphed in the xy  -plane. What is the x -coordinate of the intersection  point ( x, y) of the system?

According to the system of equations above, what is the value of X ?

Note:
Here we find the value of y from equation (1) and use it in equation (2).
We could do it the other way and receive the same answer, that is, if we find the value of y from equation (2) and use it in equation (1) to find x, we get the same value of x as found in the solution above.
Students are encouraged to try this method too.

The scatterplot above shows the number of registered voters, , x and the number of people who voted in
the  last election, y , for seven districts in a town. A line of best fit for the data is also shown. Which of the following could be the equation of the line of best fit?

The relationship between x and y can be written as y = mx , where m is a constant. If  y = 17 when x =a , what is the value of y when x = 2a ?

700 , 1200 ,1600 , 2000 , x
If the mean of the five numbers above is 1600 , what is the value of  x?

Some values of  x and their corresponding values of  y are shown in the table above, where a is a constant. If there is a linear relationship between x and y, which of the following equations represents the  relationship?

In the triangle above, a = 34. What is the value of b + c ?

Lynne has $8.00 to spend on apples and oranges. Apples cost $0.65 each, and oranges cost $0.75 each. If there is no tax on this purchase and she buys 5 apples, what is the maximum number of whole oranges she can buy?

The first year Eleanor  organized a fund-raising event, she invited 30 people. For each of the next 5 years, she invited double the number of people she had invited the previous year. If  is the number of people invited to the fund-raiser  years after Eleanor began organizing the event, which of the following statements best describes the function  ?

Clayton will mix X milliliters of a 10 % by mass saline solution with y  milliliters of a  by mass saline solution in order to create an 18%  by mass saline solution. The equation above represents this situation. If Clayton uses 100 milliliters of the 20% by mass saline solution, how many milliliters of the 10% by mass saline solution must he use?

The maximum value of a data set consisting of 25 positive integers is 84 . A new data set consisting of 26 positive integers is created by including 96 in the original data set. Which of the following measures must be 12 greater for the new data set than for the original data set?

In the equation above, a is a constant. The graph of the equation in the x y - plane is a parabola. Which of the following is true about the parabola?

The table above shows the results of a survey in which tablet users were asked how often they would watch video advertisements in order to access streaming content for free. Based on the table, which of the following is closest to the probability that a tablet user answered "Always," given that the tablet user did not answer "Never"?