Sierra and Charlie are paid $12 per hour. However, this week Charlie received a $40 bonus. Given that S and C represent the number of hours worked by Sierra (S) and Charlie (C), which expression can be used to represent their combined earnings for this week?

12+40+SC

12SC+40

12+40+S+C

12S+12C+40

The correct expression to represent their combined earnings for this week is 12S + 12C + 40.

The expression that can be used to represent their combined earnings for this week is 12S + 12C + 40.

To calculate the combined earnings for Sierra and Charlie this week, we need to multiply the number of hours each of them worked by their hourly rate and then add any additional bonuses.

Since both Sierra and Charlie are paid $12 per hour, Sierra's total earnings can be calculated as 12S (12 multiplied by the number of hours Sierra worked represented by S).

Similarly, Charlie's total earnings can be calculated as 12C.

To account for Charlie's $40 bonus, we add 40 to the total.

Therefore, the expression that represents their combined earnings for this week is:

12S + 12C + 40