Surface area of a cylinder=

=5089.38
Hello there!
15 is a term so the first digit in the code is 4.
15-3y is an expression so the second digit in the code is 5
4 5 x x x is the code right now
Now, let's solve the third puzzle:
4(2y-3)-2y=24
8y-12-2y=24
Combine like terms:
6y=36
x=6
4 5 4 x x is the code right now
The next problem:
1/3(12x-3)=7
4x-1=7
4x=8
x=2
4 5 4 2 x is the code right now
Problem 5: I think it's infinite solutions
4 5 4 2 4 is the code!
I hope it is correct! If it isn't, don't report and send me more puzzles! I would love to strain my brain!
Your friend, 
9514 1404 393
Answer:
multiply the radius by √1.2 ≈ 1.0954
Step-by-step explanation:
Let the original depth and radius be represented by 30 and r. Let the modified depth and radius be represented by 25 and r'. Assuming the pond is uniform depth, the formula for the volume of a cylinder applies. The volume of a cylinder is given by ...
V = πr²h
In this application, we want the original and modified volumes to be the same.
πr²(30) = π(r')²(25)
(r')² = r²(30/25) = r²(6/5)
r' = r√(6/5)
The radius can be multiplied by √1.2 to maintain the original volume of the pond.