Answer:
0.021943
Step-by-step explanation:
Alice solves every puzzle with a probability of 0.6
Bob solves every puzzle with a probability of 0.5
Number of puzzles given = 7
The probability of a puzzle been solved by either Alice or Bob
P = P( A U B ) = P( A ) + P( B ) - P( A n B )
= 0.6 + 0.5 - ( 0.6 * 0.5 ) = 0.8
probability of all 7 puzzles solved = (P( A ))^2 * ( P )^3 * (p(B))^2
= ( 0.6 )^2 * (0.8)^3 * (0.5)^2 = 0.04608
Finally determine the P ( choosing 5 out of 7 for both such that all the 7 are chosen )
attached below is the remaining part of the solution
