a bag contains 3 red, 6 white and 7 blue balls. What is the probility that two balls drawn are white and blue?
To find the probability of drawing two balls that are white and blue, we need to calculate the number of favorable outcomes (drawing a white ball and then a blue ball) and divide it by the total number of possible outcomes.
First, let's determine the total number of balls in the bag:
Total balls = Red balls + White balls + Blue balls
= 3 + 6 + 7
= 16
Next, we find the number of favorable outcomes, which is drawing a white ball and then a blue ball. Since there are 6 white balls and 7 blue balls, the number of favorable outcomes can be calculated as:
Favorable outcomes = Number of white balls * Number of blue balls
= 6 * 7
= 42
Now, let's calculate the total number of possible outcomes. To do this, we need to consider that after the first ball is drawn, the total number of balls decreases by 1. Thus, the total number of possible outcomes can be calculated as:
Possible outcomes = Total balls * (Total balls - 1)
= 16 * (16 - 1)
= 16 * 15
= 240
Finally, we can calculate the probability by dividing the number of favorable outcomes by the number of possible outcomes:
Probability = Favorable outcomes / Possible outcomes
= 42 / 240
= 0.175
Therefore, the probability of drawing two balls that are white and blue from the bag is 0.175 or 17.5%.