Length of the tank (L) = 25m
width of the tank (W) = 12m
Height of the tank (H) = 6m
Surface area of the 4 walls = 2(LXH + WxH)
= 2x6(25+12)
= 12x27
= 324 square meter
Surface area of the bottom = LXW
= 25x12 = 300 square meter
Total area for plastering = 324+300 = 624 squre meter
Cost of the plastering = 75 pasie/square meter
Total cost of plastering = 624x75 = 46800 paise = Rs 468.
2H(L+W)
2*6(25+12)
12(37)
444
So in short answer is 444+300=744
Then paisa 744*75=55800 paisa i.e.,558rupees