Numerous is related to Crowd. Crowd is related to People. 
Small is related to Figure. Figure is the opposite of Estimate. Estimate is a synonym of Calculate. Add is a type of Calculate. 
Numerous <--RelatedTo--> Crowd <--RelatedTo--> People 
Small <--RelatedTo--> Figure <--Antonym--> Estimate <--Synonym--> Calculate <--IsA-- Add 