Question 1122840
None worried; 0.218^3=0.0103
At least 1 worried is 1-None worried=0.9897
All will be worried is 0.4782, 0.782^3
Two will be worried is 3*.782^2*0.218=0.3999
One will be worried is 3*0.782*0.218^2=0.1115