Question 1132268
<br>
The yearly salaries form an arithmetic sequence.  The sum is<br>
(number of years) times (average salary)<br>
Because the salaries form an arithmetic sequence, the average salary is the average of the first and last year's salaries.<br>
first year salary: 2000000
20th year salary: 2000000 + 19(30000) = 2570000<br>
Total salary for 20 years:<br>
{{{20*((2000000+2570000)/2) = 10*4570000 = 45700000}}}