There is a bag filled with 5 blue and 4 red marbles. A marble is taken at random from the bag, the colour is noted and then it is replaced.
Another marble is taken at random.
What is the probability of getting 2 of the same colour?

8/18=4/9

Step-by-step explanation:

since it there is 1/6 for red marbles and 5/18 for blue marbles it works because it is 8*9=72 for the denominator and 4*3=12 so it is 12/72=1/6 and for blue it is 5/18 because it is 5*4=20 and 20/72=10/36=5/18 so it is 1/6+5/18=8/18=4/9

Hey there...

Let's solve this questions with numbers and symbols
 --> your real question

let's change them to improper fraction 
*  

Now lets simplify the problem
 
 ---> zero's from the end are cancelled out so we are left with,
will be your answer in improper fraction fraction 
or
will be your answer in mixed fraction 
or
1.3 will be your answer in decimal.

Hope this answered your question and helped you...  :-)