Search Placementyogi.com

# eLitmus Probability questions for eLitmus exam | eLitmus Questions for pH Test

:: Topics ::

 11 In a chimp zoo there are 1 billion monkeys. The probability that a monkey in the zoo has seen a banyan tree is 0.6. The probability that a monkey has seen a mango tree is 0.65. What is the minimum percentage of monkeys in the zoo who have seen both the tree ? A. 25% B. 39% C. 40% D. 60%
See Answer & Explanation Lets Discuss
Explanation

For two independent events P(A and B) = P(A)*P(B)

=> P(monkey has seen a banyan tree and monkey has seen a mango tree) = P(monkey has seen a banyan tree) * P(monkey has seen a mango tree)

=> P(monkey has seen a banyan tree and monkey has seen a mango tree) = 0.6 * 0.65  = 0.39

So the percentage of monkeys who has seen both banyan tree and mango tree = 39%

 12 What is the probability of forming a triangle from a 4x4 Matrix? A. 127/140 B. 129/140 C. 131/140 D. 123/140
See Answer & Explanation Lets Discuss
Explanation

 13 Two friends have decided to meet between 3 and 4 o clock and they have decided to wait for 15 mins to meet (for eg A have reached by 3 he will wait for 15 mins for B similarly B also ) then what is the probability of both are meeting? A. 5/16 B. 7/16 C. 9/16 D. 3/16
See Answer & Explanation Lets Discuss
Explanation

No explanation available. Let's Discuss

 14 Ram draws a card randomly among cards numbered 1-23 and keep it back.Then sam draws a card among those then what is the probality that Sam has drawn a card greater than Ram. A. 84/142 B. 84/143 C. 84/144 D. 84/145
See Answer & Explanation Lets Discuss
Explanation

If ram draws 1 then Sam has 22 choices. If ram draws 2 then Sam has 21 choices and so on..

So, the probality that Sam has drawn a card greater than Ram is

=> 1/23*22/23 + 1/23*21/23 + 1/23*20/23 + .... + 1/23*1/23

=> 1/23*[(22+21+...+10)/23]

=> 1/23*{22/2*[1+22]}/23

=> 252/529 or 84/143

 15 If a 4 digit no.is randomly chosen,then what is the probability(approximately) that it is a perfect square? A. 0.006 B. 0.007 C. 0.06 D. 0.0076
See Answer & Explanation Lets Discuss
Explanation

Total 4-digit no's that are possible, 10000-1000 = 9000
Perfect squares of 4-digit no. starts from 1024 which is the square of 32 and ends in 9801 which is the square of 99...
So No. of 4-digit numbers which are perfect squares are 99-31 = 68
Prob. will be = 68/9000 = 0.00755 = 0.0076

Hide Page Information