A survey asks: Which online services have you used in the last month:

Twitter

Facebook

Have used both
The results show of those surveyed have used Twitter, have used Facebook, and
have used both.
What percent of the people surveyed used neither Twitter nor Facebook?
Question Help: Message instructor
: Calculator

Ask by Bolton Bowers. in the United States

Mar 22,2025

Question

A survey asks: Which online services have you used in the last month:

Twitter

Facebook

Have used both
The results show of those surveyed have used Twitter, have used Facebook, and
have used both.
What percent of the people surveyed used neither Twitter nor Facebook?
Question Help: Message instructor
: Calculator

Ask by Bolton Bowers. in the United States

Mar 22,2025

UpStudy AI · Accepted Answer

Let $$ T $$ be the percentage of people who used Twitter and $$ F $$ be the percentage who used Facebook. We are given:

$$
T = 40\%, \quad F = 58\%, \quad T \cap F = 9\%
$$

Using the principle of inclusion and exclusion, the percentage of people who used at least one of the services is:

$$
T \cup F = T + F - T \cap F = 40\% + 58\% - 9\% = 89\%
$$

Finally, the percent of people who used neither service is:

$$
100\% - 89\% = 11\%
$$
11% of the people surveyed used neither Twitter nor Facebook.