By caluclating the volume of1,64,000 bricks we get10×8×4×164000=52480000 cm³
Then the cost of these bricks will be 52480000÷100=Rs.524800
Cost of painting the bricks is 52480000÷20=Rs.2624000
By adding the cost of bricks and cost of painting the bricks we get
Therefore Rs.3148800 is the answer.
Hope this helps you ........... :-)