A cylindrical tank is required to contain a gage pressure 590 kPa.The tank is to be made of A516 grade 60 steel with a maximum allowable normal stress of 150 MPa. If the inner diameter of the tank is 2 m , what is the minimum thickness, t, of the wall?

Try to divide by each prime number starting with 2. If it is divisible, keep trying the same prime number until it is not divisible. Then move on to the next prime number, 3. Keep dividing until you get 1. All the prime numbers you divided by are the prime factorization.

List of the first several prime numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29

Start with 85.

85 is not divisible by 2.

Move on to 3.

85 is not divisible by 3.

Move on to 5.

85/5 = 17

17 is a prime number, so now divide 17 by 17.

17/17 = 1

We divided just by 5 and 17.

The prime factors of 85 are 5 and 17.