Question

Question 15
A contract on construction job specifies a penalty for delay of completion beyond a certain date as follows: ₹ 200 for the first day, ₹ 250 for the second day, ₹ 300 for the third day, etc., the penalty for each succeeding day being ₹ 50 more than for the preceding day. How much money the contractor has to pay as penalty if he has delayed the work by 30 days?

Answer 1

It can be observed that these penalties are in an A.P having first term as 200 and common difference as 50.
a = 200
d = 50
Penalty that has to be paid if he has delayed the work by 30 days
$=S_{30}$
$=\frac{30}{2}\left[2\right(200)+(30-1\left)50\right]$
= 15 [400 + 1450]
= 15 (1850)
= 27750
Therefore, the contractor has to pay ₹ 27750 as penalty.