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Estimate the total number of light bulbs currently used in Delhi
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In this estimation question we have analysed the market size of the number of Golf ball that can fit in the room. Check out the step-by-step answer created by Mobiprep experts.
Estimation Question Step-1: Segmentation
Assume the room to be approximately 4 mtrs wide, 6 mtrs long and 4 mtrs in height.
(I came to this number as I know my height is 1.67 mtrs. So, I imagined how many people of my height can lie along the edge of the room.)
Therefore, Volume of the room = 400*400*600 cubic cm
= 4*4*6*10^6 cubic cm
= 96*10^6 cubic cm
Average diameter of a Golf ball is say 5 cm.
Therefore, volume of the Golf ball = 4/3*3.14*5/2*5/2*5/2 (As, Vol. of sphere = 4/3*3.14*r^3)
= 65.41 cubic cm
Now, volume covered by a Golf ball, if a cube of volume a^3 packs one Golf ball.
So, Volume of Golf ball = Volume of a cube
Therefore, 4/3*3.14*(5/2)^3 = a^3
Hence, a = 4 cm (approx)
Therefore, Volume of cube = 4*4*4 cubic cm
= 64 cubic cm
For total no. of Golf balls that can fit in the room = (Volume of the room/Volume of the cube)
= 1.5*10^6 balls
Estimation Question Step-2: Solution
Now, for the spaces left in the 4 edges of the cube is approximately 25% volume of the ball.
Therefore, total number of Golf balls that can fit in the room are (1.5*10^6 - 25%*1.5*10^6)
So, total Golf will be 3/4*15 lakhs
Therefore, total number of Golf balls that can fit in the room = 11.25 lakhs or 11 lakhs 25 thousands.