Here are a few different ways.
If the amount you are checking is in cell A1, then this nested IF statement would work:
IF(A1>=7000000,150,IF(A1>=4000000,120,IF(A1>=2000000,90,IF(A1>=1000000,60,30))))
Or you can use LOOKUP, like this:
=LOOKUP(A1,{0,1000000,2000000,4000000,7000000},{30,60,90,120,150})