Question

b) A box contains 90 dises which are numbered from 1 to 90 one disc is selected at random from the box .find the probability that it bears 1) a two-digit number 2) a perfect square number ​

Answer 1

Step-by-step explanation:

n(s)=90

Event A= a two digits number

A={10,..,90}

N(A)=81

EVENT B= NUMBER IS PERFECT SQUARE

B={1;4;9;16;25;36;49;64;81}

N(B)=9

P(A)=81/90=9/10

P(B)=9/90=1/10