Three numbers are in A.P and their sum is 69 also the product of first two numbers is 483

00 logs are stacked in the following manner : 20 logs in the bottom row, 19 in the next row, 18 in the row next to it and so on (see Fig. 5.2). In how many rows the 200 logs are placed and how many logs are in the top row?

In the bottom row = 20 logsIn the next row = 19 logsIn the row next to it = 18 logs and so on.Thus, 20, 19, 18,... form an A .P. with

a1 = 20, a2 = 19, a3 = 18

and Sn = 200