1/10 of a pole is coloured red, 1/20 is white and 1/30 part is Blue, 1/40  is black and the rest is green. If the length of the green portion of the pole is 4.75 m, then the length of the pole is:

Correct option is B

 Given: 

The length of the green portion of the pole = 4.75m 

Solution:

Let the total height of the pole 300 unit 

According to the question

Red part of the pole = 300 x$$\frac{1}{10}$$  = 30 unit 

White part of the pole = 300 $$\times \frac{1}{20}$$  =15 unit

Blue part of the pole = $$300\times\frac{1}{30}$$  = 10 unit 

Black part of the pole = $$300\times\frac{1}{40}$$  = 7.5​

Then the Greed part of the pole  = 300 -(30+15+10+7.5) = 237.5 unit 

237.5 Unit = 4.75 , 1 unit = 0.02 m 

Then the height of the = 0.02$$\times300 = 6 \ m$$​​

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