The cost per child per child is $10 more at Mr Bob's buffet than it is at Sally's pizza safari.
Answer: Option 3.
<u>Explanation:</u>
According to the data and the information that has been given in the question, the cost of four children for this birthday party at Mr Bob is $60. But the cost of hosting a birthday party at Mr Sally is $50 which is the cost of four children.
So this tells us that the cost of hosting a birthday party is expensive at Mr Bob when compared to the cost of hosting a party at Mr Sally. It is $10 more than Mr Sally.
