Answer:
The expression for 7 sundaes cost __ dollars will be: 7n
Thus, option C i.e. 7n is correct.
Explanation:
Given
A sundae cost n dollars.
To determine
7 sundaes cost _____ dollars?
It is stated that A sundae cost n dollars, it means:
The cost of one sundae = n dollars
Thus,
The cost of 7 sundaes can be calculated by multiplying 7 by n dollars.
Therefore,
The cost of 7 sundae = 7n dollars
Hence, the expression for 7 sundaes cost __ dollars will be: 7n
Thus, option C i.e. 7n is correct.