Question: Using operators plus, minus, multiplied by and divide by, and as many brackets as you want, can you do a formula which uses 3, 3, 5 and 7 to make 24? 

Each number must be used and can only be used once (so there will be two 3's).

So, for example, (3x7)+3 makes 24, but this isn't valid because the 5 wasn't used.

I don't know if this is possible, btw! It's in a game I'm playing.

Answer: 
what about this one? 

> 
>  using factorials of 3  
> 
>  $7+5+3!+3! = 24$
> 
> 
>
I also thought about : 

> 
>  $3 \* (7 - 5) ^ 3$
> 
> 
> 

Breaks the rule but hey