Question

The cost of paving the floor at the rate of Rs. 18 per $m^2$.

• A. Rs. 10239
• B. Rs. 8839
• C. Rs. 7125
• D. Rs. 5040

Answer 1

The correct option is D Rs. 5040

AM=BN=$\frac{7-5}{2}$
=$\frac{2}{2}$
=$1m$
In $△ADM$
$A{D}^2=A{L}^2+D{L}^2$
$=>A{D}^2=1^2+{2.4}^2$
$=>A{D}^2=1+5.76$
$=>A{D}^2=\sqrt{6.76}$
$=>AD=2.6m$
Perimeter of the cross section of the tunnel $=(5+2.6+2.6+7)m$
$=17.2m$
Length $=40m$
$\therefore$ area of the floor $=40\times 7$
$=280m^2$
Rate of painting $=18per{m}^2$
Cost of paving the floor=$280\times 18m^2$
=Rs. $5040$