I am very bad at excel and I hope you can help me with my equation.

I am sure it is rather simple, however not for myself as I can not figure it out.

my data as follows, for example:

cell O15 is my quantity

cell T15 is price A

cell U15 is price B

cell V15 is price C

when O15 quantity is <6, it is Price A (T15), when the quantity >5 but <11 it is Price B U15, and of course when the quantity is >10 the Price is C V15,

I have come up with the string: =IF((O15)<6,O15*t15, 0) and this is my start, but how do i connect the remaining two variables in the same string?

Your help will be greatly appreciated.