# Formula : I'd like to multiply 2 numbers and modify the result to skew higher when larger numbers are involved and lower with lower numbers.

I'm not sure of the correct terminology here so I apologize if I've missed existing answers but when I searched I didn't find what I was looking for so I hope you can help.

Here is the situation. We have a product for sale based on the addition of the height and weight of the item multiplied by a factor — let's say 3 for now.

But when the item is larger, it costs more so I want when the combined width and height are over a certain amount to multiply more than 3 and when under a certain amount, to multiple at less than 3.

I tried a simple formula like this:

(h+w) x 3 x (h+w) / 60

(the 60 above is an average width + height)

Now this is too large a skew and I wonder if I can reduce this by 1/2 the skew or more? Any ideas on how to do what I want?

Thanks!

• $\frac{(h+w)^k}{60}$. Adjust $k$ as needed. – Don Thousand Oct 19 '18 at 18:12
• I'm curious. In the case of h+w being 80, the extra multiplier would be 80/60 = 1.333333 and I would like it to be less, let's say half the increase.. so 1.167777777. Adding an exponent would increase the value by a lot more, no? – Aethon Oct 19 '18 at 18:32
• Have you tried it? You might be surprised. – Don Thousand Oct 19 '18 at 18:33
• Let's say I put a 2 as "k". 80x80/60 is MUCH higher than I'm looking... so I'm not sure what you mean.. It's been many, many years since my calculus classes and for all intents and purposes, I'm a basic math user. – Aethon Oct 19 '18 at 18:45
• OK.. using a fraction as an exponent I might be able to get closer... I'm going to play with this and see if it works well.. thanks for the tip! – Aethon Oct 19 '18 at 18:50