A study conducted by the Pew Research Center reported that 58% of cell phone owners used their phones inside a store for guidance on purchasing decisions. A sample of 15 cell phone owners is studied. What is the probability that 10 or more of them used their phones for guidance on purchasing decisions? Round your answer to 2 decimal places

The probability that 10 or more of them used their phones for guidance on purchasing decisions =   = .278

Step-by-step explanation:

Given -

A study conducted by the Pew Research Center reported that 58% of cell phone owners used their phones inside a store for guidance on purchasing decisions .

Then the probability of success is (p) = 58 = .58

the probability of failure is (q) = 1 - p = .42

sample size n = 15

Let X be the no of owners used their phones for guidance on purchasing decisions

Using the formula

The probability that 10 or more of them used their phones for guidance on purchasing decisions =  

= P(X = 10) +  P(X = 11) +  P(X = 12) +  P(X = 13) +  P(X = 14) +  P(X = 15)

= =

= =

= .1119 + .1015 + .048 + .014 + .0030 + .00028

= .278

the formula of a slope:

from a table we have

substitute:

the slope of f(x) is -1.

the graph of funcfion g(x) is a horizontal line. the slope of a horizontal line is equal 0. therefore the slope of g(x) is 0.

-1 < 0