Q27 of 31 Page 1

Cards marked with numbers 3, 4, 5, ………..…., 50 are placed in a bag and mixed thoroughly. One card is drawn at random from the bag. Find the probability that number on the card drawn is:

a. Divisible by 7


b. A perfect square


c. A multiple of 6

We know,


Probability of an event


a. Total cards from 3 and 50 = 50 – 3 + 1 = 48


Cards having number divisible by 7 = {7, 14, 21, 28, 35, 42, 49} = 7


Probability (Number is divisible by 7)


b. Total cards from 3 and 50 = 50 – 3 + 1 = 48


Cards having a perfect square = {4, 9, 16, 25, 36, 49} = 6


Probability (Number is perfect square)


c. Total cards from 3 and 50 = 50 – 3 + 1 = 48


Cards having number multiple of 6 = {6, 12, 18, 24, 30, 36, 42, 48} = 8


Probability (Number is multiple of 6)


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