How do I enter formula sum(range+range)*0.15 sumif(range>=3)

[tkw]

I'm not sure how to enter this formula:

I want to add two ranges and multiply the total by 0.15, but only if the
range of another cell is "less than or equal to" 3.

 

[Luke M]

If I interpret you correctly:

=SUM(Range1,Range2)*IF(SUM(Range3)<=3,0.15,1)

My assumption was that your wanted the sum of the first two ranges
regardless, and the multiplcation factor was what was dependend upon the
value of range3.

 

[Dave Peterson]

One way:
=(a1+b1)*if(c1<=3,0.15,1)

Multiplying by 1 won't change the result of the addition.