Question

I need to find the probability in this word sentence. A bag contains three red marbles and seven blue marbles. You randomly pick a marble and then return it to the bag before picking another marble. Both and second marbles are red.

Answer 1

we have

3 red marbles

7 blue marbles

then

`(3)/(10)*(3)/(10)=(3*3)/(10*10)=(9)/(100)`

answer: 9/100