Answer:0.2
Step-by-step explanation: Let the two companies be A and B
Pa = probability of getting a job offer from only company A
Pb = probability of getting a job offer from only company B
Pbb = probability of getting a job offer from both companies
Pn = ProbabityProbability of getting a job from neither companies
The relation could be combined using :
Pbb+Pa+Pb+Pn=1
Pn = 0.3
(Pa + Pb) =probability of offer from exactly one of A or B = 0.5
Pbb + 0.5 + 0.3 = 1
Pbb+0.8=1
Pbb=1-0.8
Pbb = 0.2