The amount that Tony and his friend's will spend at the dell can be found by
writing an expression for the total cost.
The number of Toby's friends = 3
Number of people that ate lunch, n = Toby + His friends = 1 + 3 = 4
The cost of the sandwiches and drinks
[tex]\begin{tabular}{|c|c|c}Item&Cost(\$)\\Sandwich&2.75\\Drink &1.25\end{array}\right][/tex]
The expression that gives the amount Toby and his friends spend altogether is therefore;
Amount spent = n × (Cost of a sandwich + cost of a drink)
Which gives;
4 × (2.75 + 1.25) = 16
Learn more about mathematical expressions here:
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