A man started to work in 1985 at an annual salary of $8,000. He received a $600 raise each year. How much was his salary in 2012?

so this an arithmetic sequence

with
a = 8000
d = 600
n = 27

term (27) = a + 26d
= 8000 + 26(600) = $23,600

To calculate the man's salary in 2012, we need to determine how many years have passed since 1985 and calculate the total amount of raises he received.

First, let's calculate the number of years between 1985 and 2012:
2012 - 1985 = 27 years

Next, we need to calculate the total amount of raises he received over 27 years:
27 years × $600/raise = $16,200

To find his salary in 2012, we add the total amount of raises to his starting salary in 1985:
$8,000 + $16,200 = $24,200

Therefore, his salary in 2012 was $24,200.