Answer: Probability of trucks having both defects is 4%.
Step-by-step explanation:
Since we have given that
Probability of trucks having defective brake linings only = 6%
Probability of trucks having defective steering only = 3%
Probability of trucks having neither defect = 87%
Probability of trucks having either defect - 100 - 87 = 13%
Let the probability of trucks having both defects be 'x'.
P(defective brake lining) = P(B) = 0.06+x
P(defective steering) = P(S) = 0.03+x
So, Probability of the trucks having both defects is given by
So, Probability of trucks having both defects is 4%.