Final answer:
The expression that correctly represents the phrase 'The product of 3 and the sum of 7 and s' is 3(7 + s). This is a typical middle school level algebra problem demonstrating the use of addition and multiplication with variables.
Step-by-step explanation:
The expression that represents the phrase 'The product of 3 and the sum of 7 and s' is found by first identifying the operation indicated by the word 'sum', which refers to addition, and then by recognizing the word 'product' which indicates multiplication. So, according to the order of operations, you first need to find the sum of 7 and s, and then multiply the result by 3. The correct expression is therefore 3(7 + s).
To demonstrate, this means you add 7 and s together first: 7 + s. Then you take that result and multiply it by 3: 3 × (7 + s), which translates to 3(7 + s) algebraically.