 Hello and how are you all? The question says a bag contains 5 red balls and some blue balls. If the probability of drawing a blue ball is double that of a red ball, find the number of blue balls in the bag. So let us discuss this question. Here let the number of blue balls be X. The number of red balls is given to us in the question as 5, right? So therefore we can say that the total number of balls in the bag are equal to blue balls plus red balls. Now let us find out the probability of a red ball. That will be equal to number of red balls divided by total number of balls in the bag that is 5 upon X plus 5 and probability of picking up a blue ball will be equal to number of blue balls that we have taken in the question as X divided by the number of total balls in the bag that is X plus 5. Now according to the question we are given that if the probability of drawing a blue ball is double that of a red ball. That means probability of a blue ball that is X upon X plus 5 is double than that of a red ball that is 5 upon X plus 5. Then we need to find out the value of X that is the number of blue balls in the bag. So let us solve the following question. We have X upon X plus 5 equal to opening brackets 10 upon X plus 5 and simplifying we have the value of X as 10. So we can write down therefore the number of blue balls in the bag are 10. This completes the session. Hope you understood the whole question well and enjoyed it too. Have a nice day ahead.