Mensuration Ques 27
Question
The sum of the dimensions of a room (i.e. length, breadth and height) is 18 metres and its length, breadth and height are in the ratio of $3: 2: 1$ respectively. If the room is to be painted at the rate of Rs. 15 per $m^{2}$, what would be the total cost incurred on painting only the four walls of the room (in Rs.)?
(1) 3250
(2) 2445
(3) 1350
(4) 2210
(5) 2940
(IBPS RRBs Officer CWE (Pre.))
Show Answer
Correct Answer: (3)
Solution: (3)
$l+b+h=18$ metre
$l: b: h=3: 2: 1$
Sum of the terms of ratio $=3+2+1=6$
$\therefore$ Length $=\frac{3}{6} \times 18$ $=9$ metre
Breadth $=\frac{2}{6} \times 18=6$ metre
Height $=3$ metre
$\therefore$ Area of the four walls of room $=2 \times h(l+b)$
$=2 \times 3(9+6)=90$ sq. metre.
$\therefore$ Total cost of painting $=$ Rs. $(15 \times 90)=$ Rs. 1350
BETA
