A room has three lightbulbs. Each one has a 9%
probability of burning out within the month. Write each probability as a percentage.
What is the probability that all three will be lit at the end of the month?
Each lightbulb has a 91% chance of NOT burning out within the month (100% - 9% = 91%).
To find the probability that all three will be lit at the end of the month, we need to multiply the probabilities of each individual lightbulb not burning out:
0.91 x 0.91 x 0.91 = 0.7538
This means there is a 75.38% chance that all three lightbulbs will still be lit at the end of the month.