Final answer:
There are 84 different ways the art gallery can choose and display 6 paintings out of 9.
Step-by-step explanation:
To find the number of different ways the art gallery can choose and display 6 paintings out of 9, we can use the concept of combinations. A combination is a selection of objects without regard to the order in which they are chosen.
The formula to calculate combinations is given by C(n, r) = n!/((n-r)! * r!), where n is the total number of objects and r is the number of objects to be chosen.
Using this formula for the given problem, we have:
C(9, 6) = 9!/((9-6)! * 6!) = 9!/3! * 6! = (9 * 8 * 7)/(3 * 2 * 1) = 84
Therefore, there are 84 different ways the art gallery can choose and display 6 paintings out of 9.