# Cards marked with numbers 5 to 100 are placed.one card is drawn from this . find the probblity that the no. on the card is 1) a perfect square 2) a multiple of 7 3 ) a prime no. less than 25

2
by deeeeep

2015-03-09T12:28:00+05:30

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
We have totally  100-5+1 = 96 cards in the pack.

Perfect squares between 5 and 100 are :
9, 16, 25, 36, 49, 64, 81, 100  => there are 8 of them.

1) Probability that a randomly drawn card from the pack is a perfect square is
8/96 = 1/12

2) Multiples of 7 between 5 and 100:
7 * 1 to  7 * 14      => there are 14 cards.
Probability that a randomly drawn card is numbered with a multiple of seven:
14/96 = 7/48

3) Prime numbers < 25 are :
2, 3, 5, 7, 11, 13, 17, 19, 23 :  so probability = 9/96 = 3/32

2015-03-09T12:34:32+05:30
Probability= number of favourable events /total no.of events or possibilities......In this case the total no. Of events are 96(total no. Of cards).... No. Of perfect square no between 5 and 100 is 8.(9,16,25,36,49,64,81,100)....,Thereof the probability for 1) is 8/96 or 1/12....the no.of multiples of 7 till 100 is 14(use table I.e 7*14=98)..the probability for 2) is 14/96 or 7/48...No.Of prime numbers less than 25 is 7 ( starting from 5..,,..5,7,11,13 ,17,19,23) thereof the probability for 3) is 7/96