Question

there are two concentric circles A and B of radius 5 and 10 cm on a board for a contest of archery . An arrow shot by yajuvendra will certainly hit inside the larger circle. find the probability of the following events. 1. the arrow will hit inside the circle A2. the arrow will hit between the two circles A and B

Answer 1

Answer: 1. 0.25 and 2. 0.75.

Step-by-step explanation: As shown in the attached figure, we are given two concentric circles A and B with centre 'O', radius 5 cm and 10 cm respectively.

So, area of circle A is given by

$a_1=\pi\times 5^2=25\pi$

and

area of circle B is

$a_2=\pi\times 10^2=100\pi.$

So, the areq lying between circle A and B is

$a_3=a_2-a_1=75\pi.$

Therefore, the probability that the arrow will hit inside circle A is

$p_1=\dfrac{25\pi}{25\pi+75\pi}=\dfrac{1}{4}=0.25$

and the probability that the arrow will hit between the two circles A and B is

$p_2=\dfrac{75\pi}{25\pi+75\pi}=\dfrac{3}{4}=0.75.$

Thus, the probabilities are 0.25 and 0.75.

Answer 2

Answer:

3. Write note on any one programme broadcasted by All India Radio (AIR), that awakens the masses.