I know this question is very simple but I will ask it hope not to misunderstand, recently I involved in a test which one of the questions like below:

a company revenue growth percentage were 30%, 10% and 90% within 3 years continuously what is the percentage of average yearly growth.

I know average is adding all numbers and divide by the number of years, but in the test there were not answer options like that.

the answer options were 25, 20, 35, 40. I don't remember exactly.