Is there a way to create an evaluative formula that sort of uses and If/Then.

I want to have a cell apply a number (ultimately its a multiplier) based on the value of another cell.

I have 5 cells that will have data inputed manually. A column cell at the end of those cells does the avg of the 5. The next cell is for assigning a multiplier based on what the avg number is.

For simplified example
If cell number is less than 10,000, put in a number 1
If cell number is 10,001-20,000, the number should be 1.3
iF cell number is 70,000-79,000, the number would be 3.5

The numbers don't matter so much as how to fill in the multiplier automatically based on what the avg came out to be.