A playground is being designed where children can interact with their friends in certain combinations.

If there is 1 child, there can be 0 interactions.
If there are 2 children, there can be 3 interactions.
If there are 3 children, there can be 9 interactions.
If there are 4 children, there can be 18 interactions.

How many interactions will there be for 9 children?

Question

A playground is being designed where children can interact with their friends in certain combinations. 

If there is 1 child, there can be 0 interactions. 
If there are 2 children, there can be 3 interactions. 
If there are 3 children, there can be 9 interactions. 
If there are 4 children, there can be 18 interactions. 

How many interactions will there be for 9 children?

anonymous · Answer

these are the options 

135

 84

 93

 108

anonymous · Answer

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