Formula to add, based on number variables

Hi
Can someone help me with a formula please?

A1 holds a number and B2 a different.
Bases on the number in A1, I need to add B1 with a given number, and get the result in C1.
Say A1 Is less than 100. Then I need to add B1 with 2.
If A1 is less than 500 but more than 100, then I need to add B1 with 1,5
If A1 is less than 2000 but more than 500, then I need to add B1 with 1,2
And If A1 is more than 2000, then I need to add B1 with 1,1
thank you

i am using excel 2013

Try this ...

=B1+LOOKUP(A1,{0,100,500,2000},{2,1.5,1.2,1.1})

Did not work for me...?
Dont know what’s wrong, but i cant use the formula you have here (also tried to translate "lookup" to lokal language).

Change "," to ";" ?

Like this?
(A1;{0,100,500,2000};{2,1.5,1.2,1.1})
or
(A1;{0;100;500;2000};{2;1.5;1.2;1.1})

this solution
(A1;{0,100,500,2000};{2,1.5,1.2,1.1})
gives me autocorect
(A1;{01005002000};{2,1.5,1.2,1.1})

Thx.
Got it