A contract on construction job specifies a penalty for delay in completion of the work beyond a cert...........

Quantitative Aptitiude (CLAT) Time and work

A contract on construction job specifies a penalty for delay in completion of the work beyond a certain date is as follows: Rs. 200 for the first day, Rs. 250 for the second day, Rs. 300 for the third day etc., the penalty for each succeeding day being 50 more than that of the preceding day. How much penalty should the contractor pay if he delays the work by 10 days?

Rs. 4950

Rs. 4250

Rs. 3600

Rs. 650

Explanation:

The penalty for delay on first day is 200, for second day is 250, for third day is 300 and so on. The penalties form an arithmetic progression (AP) with a common difference of 50 and first element (a) as 200. The sum of penalties for 10 days is thus same as the sum of numbers in the A.P. with n as 10. Sum of AP (formula) = n/2 [2a + (n-1) d] = 10/2 [ 2 X 200 + (10-1) X 50 ] = 4250