Question

100 pens are to be packed in packets such that total number of packets are in odd number and number of pens packed in each packet should also be in odd number . Find the no. of pens in each packet.​

Answer 1

Step-by-step explanation:

Total no. of pens=100

No. of defective pens =10

No. of non defective pens=100−10=90

P(atmost 1 is defective)= P(0 defective)+P(1 defective)

=

100

90

×

100

90

×

100

90

×

100

90

×

100

90

+

5

C

1

×(

10

1

)×(

100

90

)

4

=(

10

9

)

5

+

2

1

(

10

9

)

4