Question

A number is choosen at random from first 25 prime number find the probability that the number is not a prime​

Answer 1

The first 25 no. are: 1,2,3,,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25)

therefore , n= 25

Now,

let the event A be the no. which are not prime i.e, (4,6,,8,9,10,12,14,15,16,18,20,21,22,24)

therefore,

p( getting event A)= n

p= 14/25

Answer 2

Answer:

P(not a prime number from first 25 numbers ) = 16/25

Step-by-step explanation:

we know that first 25 numbers are :

1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25.

FROM THESE ONLY  9 NUMBERS ARE PRIME .

SO ,  PROBABILITY OF NOT GETTING A PRIME NUMBER ⇒ TOTAL NO. OF NOS. - NUMBER OF PRIME NUMBERS = NO. OF NUMBERS THAT ARE NOT PRIME .

⇒ P (NOT GETTING A PRIME NUMBER) = 25 -9 /25 = 16/25 .

HOPE IT HELPS