Question

Elementary and secondary schools were classified by the number of computers they had.

Computers 0-24 25-49 50-74 75-99 100+
Schools 752 3352 18865 14016 46805
Choose one of these schools at random. Find the probability that it has
a) 75 or more computers.
b) Less than 75 computers.
c) Less than 100 computers.

Answer 1

`Probability = 0.7259`

`Probability = 0.2741`

`Probability = 0.4414`

Explanation:

Given

The table

First, we calculate the amount of schools

`Total = 752 + 3352 + 18865 + 14016 + 46805`

`Total = 83790`

Solving (a): Probability of 75+ computers.

From the given table, schools with 75 or more computers have the population of:

`75\ or\ more = 14016 + 46805`

`75\ or\ more = 60821`

The probability is calculated as:

`Probability = (75\ or\ more)/(Total)`

`Probability = (60821)/(83790)`

`Probability = 0.7259`

Solving (b): Probability of less than 75 computers.

From the given table, schools with less than 75 computers have the population of:

`Less\ than\ 75 = 752 + 3352 +18865`

`Less\ than\ 75 = 22969`

The probability is calculated as:

`Probability = (Less\ than\ 75)/(Total)`

`Probability = (22969)/(83790)`

`Probability = 0.2741`

Solving (c): Probability of less than 10 computers.

From the given table, schools with less than 100 computers have the population of:

`Less\ than\ 100 = 752 + 3352 +18865+14016`

`Less\ than\ 100 = 36985`

The probability is calculated as:

`Probability = (Less\ than\ 100)/(Total)`

`Probability = (36985)/(83790)`

`Probability = 0.4414`