Find the indicated conditional probability using the following two-way table:
Grade
Drive to school
Take the bus
Walk
Sophomore
2
25
3
Junior
13
20
2
Senior
25
5
5
P( Drive to school | Senior ) = [?]
Round to the nearest hundredth.

Given:

The two way table.

To find:

The conditional probability of P(Drive to school | Senior).

Solution:

The conditional probability is defined as:

Using this formula, we get

                     ...(i)

From the given two way table, we get

Drive to school and senior = 25

Senior = 25+5+5

           = 35

Total = 2+25+3+13+20+2+25+5+5

         = 100

Now,

Substituting these values in (i), we get

Therefore, the required conditional probability is 0.71.

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify