Given that the cost of inviting 7 guests is $35, then the cost of inviting only one is:
[tex]\frac{35}{7}=5[/tex]dollars.
Therefore, the cost of inviting 10 guests is:
[tex]10*5[/tex]dollars.
Simplifying the above result, we get:
[tex]50[/tex]dollars.
Answer: $50.