A box contains 5 white and 3 black balls. If one ball is drawn and it is black,
Practice Questions
Q1
A box contains 5 white and 3 black balls. If one ball is drawn and it is black, what is the probability that the next ball drawn is white?
5/7
3/8
5/8
1/2
Questions & Step-by-Step Solutions
A box contains 5 white and 3 black balls. If one ball is drawn and it is black, what is the probability that the next ball drawn is white?
Correct Answer: 5/7
Step 1: Start with the total number of balls in the box. There are 5 white balls and 3 black balls, making a total of 8 balls.
Step 2: One ball is drawn and it is black. This means we have removed 1 black ball from the box.
Step 3: After removing the black ball, count the remaining balls. There are still 5 white balls and now only 2 black balls left.
Step 4: Now, calculate the total number of balls left in the box. There are 5 white + 2 black = 7 balls remaining.
Step 5: To find the probability of drawing a white ball next, use the formula: Probability = (Number of favorable outcomes) / (Total number of outcomes).
Step 6: The number of favorable outcomes (drawing a white ball) is 5, and the total number of outcomes (total balls left) is 7.
Step 7: Therefore, the probability of drawing a white ball next is 5/7.
Conditional Probability – The probability of an event occurring given that another event has already occurred.
Counting Principles – Understanding how to count the remaining outcomes after an event has taken place.
