Question

- Two numbers are selected at once from
the set of integers 1 to 20. What is the
probability that the product of the
numbers will be 24 ?​

Answer 1

Answer:

Correct option is

D

0.55

Total number of cases obtained by taking multiplication of only two numbers out of 100=

100

C

2

Out of 100(1,2,...,100) given numbers, there are the numbers 3,6,9,12...,99

which are 33 in numbers such that when any one of them is multiplied with any of the remaining 67 numbers

as any two of these 33 are multiplied, the resulting product is divisible by 3.

Then the pairs of numbers whose product is divisible by 3=

33

C

1

×

67

C

1

+

33

C

2

Hence, the required probability=

100

C

2

33

C

1

×

67

C

1

+

33

C

2

=

4950

2739

=0.55

plz make me as brainlieast