Do you use data on a cellphone? You may have a maximum amount of data you can use without having
to pay more.
Suppose a family data plan includes 10 gigabytes of
shared data and costs $80 per month. Any additional
data usage is billed at $15 per gigabyte. A certain
family wants to spend at most $125 on their bill each
month. You could use an inequality to find that the
family can use at most 3 additional gigabytes of data.