Question 9

A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marble taken out will be (i) red ? (ii) white ? (iii) not green?

Answer

**Total no. of marbles = 17**

(i) Total no. of red marbles = 5

Probability of getting red marbles = 5/17

(ii) Total no. of white marbles = 8

Probability of getting white marbles = 8/17

(iii) No. of not green marbles

= total no. of marbles – no. of green marbles

= 17 – 4= 13

Probability of getting not green marbles = 13/17

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Find the zeroes of the following quadratic polynomials and verify the relationship between the zeroes and the coefficients.

(i) x

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Refer to Example 13. (i) Complete the following table:

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- Q:-
Two poles of equal heights are standing opposite each other on either side of the road, which is 80 m wide. From a point between them on the road, the angles of elevation of the top of the poles are 60° and 30°, respectively. Find the height of the poles and the distances of the point from the poles.

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- NCERT Chapter