Question

A bag contains red and yellow cubes in the ratio of 3:4. What is the probability that a red cube is picked at random from the bag?

Answer 1

Explanation:

ok Let me explain :

Your argument of saying that the prob is 1/2 because there are 2 colors.

Had there been red, blue and green cubes you would have ended up calculating the prob as 1/3.

But this concept is wrong.

Prob is the chance occurrence of an event given many such events.

here since we have 4 cubes , the chance to pick any one is equal and that is 1/4

chance of picking a blue cube (1/4)*1 ....since we have one blue cube

chance of picking a red cube (1/4)*3 ....since we have one red cubes

You can think in a simple manner also, when something is greater in number (3>1) , the chances to pick that would obviously be more , so the probability cannot be half.