Answer:
41% probability that he will be bitten
Step-by-step explanation:
We have these following probabilities:
A 30% probability that the hiker does not bring the repellant.
A 100-30 = 70% probability that the hiker brings the repellant.
If he brings the repellant, a 20% probability of being bitten.
If he forgets the repellant, a 90% probability of being bitten.
What is the probability that he will be bitten
Two cases:
Bitten with the repellant(20% of 70%)
Bitten without the repellant(90% of 30%). So
P = 0.2*0.7 + 0.9*0.3 = 0.41
41% probability that he will be bitten
