Question

Q1,--Find median and mode of the 2 messages received on 9 consecutive days 15, 11, 9, 5, 18, 4, 15, 13, 17.
1-13, 18
2- 15, 16
3-18, 15
4-13, 6

Q2--A coin is thrown up 4 times. The probability that tails turn up in 3 cases is
1-none of the above
2- 1/3
3-1/2
4- 1/4

Answer 1

1)

Mode is the number which is repeated more in the given set of numbers

In the given list, number "15" repeated itself twice while other numbers appear only once

So Mode is "15"

Median is the middle number in the given set of numbers

Given set of numbers is 15, 11, 9, 5, 18, 4, 15, 13, 17

First we have to arrange them in numerical order

4, 5, 9, 11, 13, 15, 15, 17, 18

There are 9 numbers and the median will be 5th number

So the 5th is "13"

Answer must be 13 & 15

But the option isn't available

So we can conclude that median is derived without arranging the given set of numbers in numerical order (which is not correct), then the median will be "18" (as it comes in 5th place in given order)

So th answer is Option 3 - "18" & "15"

2)

Number of times a coin turns to tail when it is tossed 4 times = C(4,n)

We want it to be 3 times

So C(4,3) is required value

C(4,3) = 4!/3! = 4

Total number of probabilities if a coin tossed for 4 times are 2^n (2 power n)

= 2^4

= 16

So the probability to get three tails when the coin is tossed 4 times is 4/16 or 1/4

So answer is Option 4