Answer:
The total number of balls in the pyramid will be 55.
Step-by-step explanation:
Cannonballs are stacked In a pyramid shape with a base of 5 cannonballs on a side.
Therefore, at the base, the number of balls is 5².
In the layer above the base layer, there are 4 balls on each side.
So, in the layer above the base layer, the number of balls is 4².
Similarly, in the next levels, the number of balls will be 3², 2² and 1.
Therefore, the total number of balls in the pyramid will be (5² + 4² + 3² + 2² + 1) = 55. (Answer)
Answer:
480,700 sets (first choice)
Step-by-step explanation:
If all 25 questions are different,
When order of selection counts:
P(25,7)
= 25!/(25-7)!
= 15511210043330985984000000/6402373705728000
= 2422728000
When order of selection does not count count:
C(25,7)
=25!/(7!*(25-7)!)
=15511210043330985984000000/(6402373705728000*5040)
= 480,700
Hope this helps, have a nice day.
