In a theater, the first row has 17 seats and each row has 3 more seats than previous row. If the last row has 44 seats, what is the total number of seats in the theater?	Choose the correct choice from the following.
A) 265  B) 275  C) 285  D) 295  E) 305
The number of seats in the theater is   17 + (17+3) + ...+ (17+27)=   10(17) + 3(1+2+...+9)=   10(17) + 3(9)(10)/2= 170 + 135= 
<gadget id="calculator">170 + 135</gadget>
<output>305</output>
305   The answer is 305.
<result>E</result>
In a theater, the first row has 17 seats and each row has 3 more seats than previous row. If the last row has 44 seats, what is the total number of seats in the theater?