Answer:
[tex]\$3000+\$6000=\$9000[/tex]
Step-by-step explanation:
He has a raise of $400 at the end of each year, the we have to find how much is the total amount raised during the 15 years, then:
[tex]\$400\times 15=\$6000[/tex]
The during the 25 years he has a total raised of $6000 as the salary during the first years was $3000, the salary during the 15th year is:
[tex]\$3000+\$6000=\$9000[/tex]
