Quant-Cost

A tank is 25 m long, 12 m wide and 6 m deep. The cost of plastering its walls and bottom at 75 paise per sq. m, is:
a) Rs. 456
b) Rs. 458
c) Rs. 558
d) Rs. 568

 

sol>

Here l=25m,b=12m and h=6m

so for 

2walls area is 2*[length*height]=2*[25*6]=300Sq.m

another 2 walls area is =2*[width*height]=2*[12*6]=144Sq.m

for 1 wall which is base , area is=25*12 =300Sq.m

 

sum of their area is =300+300+144=744

Now for plastering of 1 side cost is 75paisa= .75 rs

then for our area cost=.75*744 =558

 

is the ans.