Question 239702
The answers are: 46, 64, and 85.
.
When you paid the 2nd penny, you got 3 more gumballs.
When you paid the 3rd penny, you got 6 more gumballs.
When you paid the 4th penny, you got 9 more gumballs.
When you paid the 5th penny, you got 12 more gumballs.
So it is fair to expect that:
when you pay the 6th penny, you'll get 15 more than what you already have.
when you pay the 7th penny, you'll get 18 more than what you already have.
when you pay the 8th penny, you'll get 21 more than what you already have.