5. 155/5=31
1.55
As 155 is ending with 5 then it can be divided by 5 thus it's not a prime number 155 = 5 x 31
0.0323
5
25.8333
The number 31 can go into the number 155 a total of 5 times.
155
155
A prime number is a number that is evenly divisible only by itself or 1.155 can be evenly divided by 5 (155/5=31), so is not a prime number.
b/5 = 31 Therefore, b = 31 x 5 b = 155
0.0016