A box contains 10 light bulbs, of which 3 are defective. If one bulb is selected
Practice Questions
Q1
A box contains 10 light bulbs, of which 3 are defective. If one bulb is selected at random, what is the probability that it is not defective?
3/10
7/10
1/2
1/3
Questions & Step-by-Step Solutions
A box contains 10 light bulbs, of which 3 are defective. If one bulb is selected at random, what is the probability that it is not defective?
Step 1: Identify the total number of light bulbs in the box. There are 10 light bulbs.
Step 2: Identify how many of those light bulbs are defective. There are 3 defective bulbs.
Step 3: Calculate the number of non-defective bulbs by subtracting the number of defective bulbs from the total number of bulbs. This is 10 - 3 = 7 non-defective bulbs.
Step 4: Write down the formula for probability. Probability of an event = (Number of favorable outcomes) / (Total number of outcomes).
Step 5: Substitute the values into the formula. The number of favorable outcomes (non-defective bulbs) is 7, and the total number of outcomes (total bulbs) is 10.
Step 6: Calculate the probability. This is 7 (non-defective bulbs) divided by 10 (total bulbs), which equals 7/10.
Probability – The likelihood of an event occurring, calculated as the number of favorable outcomes divided by the total number of possible outcomes.
Complementary Events – Understanding that the probability of an event not occurring can be found by subtracting the probability of the event occurring from 1.
