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Probability

Question
CBSEENMA9003499
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The length, breadth and height of a cuboid are 20 m, 24 m, 12 m respectively. The dimensions of length, breadth and depth are increased by 15%, 25% and 50% respectively. What is the ratio between the volume of the original cuboid and the new cuboid.  

Solution

For original cuboid
Length (l) = 20 m Breadth (b) = 24 m Height (h) = 12 m Volume (V1) =lbh
= 20 x 24 x 12 m3 = 5760 m3
For new cuboid
Length (L)  = 20m + 20 X 15 over 100 space m
                 = 23 m
Breadth (B) = 24 m + 24 X 25 over 100 space straight m
                 = 30 m
Height (H) = 12m + 12 X 50 over 100 space m
                = 18 m
therefore   Volume (V2) = LBH
                          = 23 x 30 x 18
                          = 12420 m3
therefore    Required ratio = straight V subscript 1 over straight V subscript 2 equals 5760 over 12420 equals 32 space colon space 69

1 over 10 equals fraction numerator 32.4 over denominator 10 end fraction space straight m cubed equals 3.24 space straight m cubed
therefore  Volume of wall occupied by bricks
            = 32.4 m3 - 3.24 m3

            equals space 29.16 space straight m cubed
therefore   Number of bricks
          equals space fraction numerator 29.16 cross times 100 cross times 100 cross times 100 over denominator 2160 end fraction equals space 13500
Cost of bricks
 
          equals 225 over 100 cross times 13500

          = र 30375

 

 

Some More Questions From Probability Chapter

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