I'm not a wiz at math and this problem has me a little stumped. I need the average score out of 5 but it's a little different how I do it.
I have 5 fields, field one is rating one, field two is rating two, all the way up to field 5.
I need to grab the average of all these fields together, this is currently what I have.
Sorry, it's in programming syntax
round((($rating_one / 5) + ($rating_two / 5) + ($rating_three / 5) + ($rating_four /5) + ($rating_five / 5) / 5));
So I divide each field by 5, and add them together and then divide the total amount of the fields for the average. The problem is I need it to be 1-5, and I keep getting 109.
Here are the numbers in the fields
13
432
42
33
23
What am I doing wrong? If you need more details, I'll happily provide (or try) more.
If you know the ranges for each field, the simplest thing is to first scale them so they are all out of $5$, and then average them.
To convert a quantity $Q$ that takes values between $a$ and $b$ to a quantity that takes values between $0$ and $N$ linearly, you compute $$\frac{N(Q-a)}{b-a}.$$ Note that $Q-a$ takes values between $0$ and $b-a$, so dividing by $b-a$ gives you a number between $0$ and $1$, and multiplying by $N$ gives you a number between $0$ and $N$.
Say the first field is takes values from $0$ to $N_1$, the second from $0$ to $N_2$, the third to $N_3$, the fourth to $N_4$, and the last to $N_5$ (which may or may not be different). Then to convert them to be out of $5$ and then averaging them, you can take $$\frac{\text{Field 1}}{N_1} + \frac{\text{Field 2}}{N_2} + \frac{\text{Field 3}}{N_3} + \frac{\text{Field 4}}{N_4} + \frac{\text{Field 5}}{N_5}.$$ If you then need it to be an integer, you can round; this may give you $0$ as the answer, which you may or may not want. (There is no multiplication and division by $5$ because here you have five fields, each out of five, so the multiplication and division by $5$ cancel each other out).
In general, for $k$ fields, you would take $$\frac{5}{k}\left(\frac{\text{Field 1}}{N_1} + \frac{\text{Field 2}}{N_2} + \cdots + \frac{\text{Field }k}{N_k}\right).$$