According to Mr. Bock, 67% of all students at LHS play sports. Suppose we are interested in the proportion of the 100 students in the East Atrium play sports. (a) Is the normal approximation to the proportion pˆ = r / n valid? Explain.

(b) What is the probability that the proportion of those in the East Atrium who play sports is at least three fourths?

(c) What is the probability that the proportion of those in the East Atrium who play sports is no more than 60%?

(d) What is the probability that the proportion of those in the East Atrium who play sports is between 60% and 75%?

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places