Question

The probability of selecting a rotten apple randomely from a heap of 900 apples is 0.18.What is the number of rotten apples in the heap?

Answer 1

Let's number of rotten apple be 'x'
then total number of apples = 900
P( rotten apple) =
no. of rotten apple/Total no. of apple
p( rotten apple) = 0.18 (given)
so x /900 = 0.18
x= 162
Number of rotten apple = 162

Answer 2

probability P (E) =     favourable outcomes
                                  -----------------------------
                                    total outcomes    

probability = 0.18
total  = 900
let number of rotten apples be "x"

substitute them in the formula we get,

0.18 = x/900
x = 0.18 * 900
x = 162.
thus number of rotten apples = 162

hope it helps!!