Two seperate discount amount is not added correctly

Question

I noticed some weird problem in my cart with discount.

I applied two discounts in my cart. One is for online payment, i.e. 10% and another one is for coupon i.e. 5%. So when I applied these two discounts separately everything works fine. But when both discounts applied together, then there is difference of 0.5%. I mean 10+5=15 i.e. total discount should apply to my cart is 15%, but only 14.5% is reflected in my cart. Why 0.5% is deducted?

There is no tax and other rule applied on website.

Answer 1

You have asked WHY ?

Because first 10% discount then on discounted price it applies 5%.

Let price is 100,

so 10% of 100 is 10 Now discounted price is 90.

Now 5% of that price (means 90) is 4.5 Now final price is 85.5.