Four families went out for lunch. The total food bill came to $167. The families also left a $30 tip for the
waitress. If each family spent the same amount, about how
much did each family spend on dinner? Explain how you
found your answer.

If the total doesn't include the tip, and the tip isn't included in how much the families each spent, they spent $41.75 each on their food bill.

If the total includes the tip, each family spent $34.25 on their food bill and $7.50 on the tip for the waitress.

If the total doesn't include the tip, but you want to include the tip, each family spent $49.25 on the food bill AND tip.

167/4 = 41.25
(167-30)/4 = 34.25
30/4 = 7.50
(167+30)/4 = 49.25

You need to show the graph