The rent in an apartment building was increased from $425 to 467.50. What was the percent of the increase?

To find the percent of the increase, we can use the following formula:

Percent increase = (Increase in value / Original value) * 100

In this case, the increase in value is $467.50 - $425 = $42.50.
The original value is $425.
So, the percent increase is (42.50 / 425) * 100 = 10%.

Therefore, the percent of the increase in rent is 10%.