A swim club charges a one-time registration fee of $30 plus $18 per month to maintain the membership. What is the total charge for a membership for t years?

A. 18(t + 30)
B. t(12 x 18) + 30
C. t x 18 + 30
D. $126

To find the total charge for a membership for t years, we need to consider the one-time registration fee of $30, as well as the monthly maintenance fee of $18.

First, we need to calculate the total cost of the monthly maintenance fee for t years. Since there are 12 months in a year, the total number of months for t years would be 12t.

To get the cost of the monthly maintenance fee for t years, we multiply the monthly fee of $18 by the total number of months (12t): 18 * (12t) = 216t.

Next, we add the one-time registration fee of $30 to the cost of the monthly maintenance fee for t years: 216t + 30.

Therefore, the total charge for a membership for t years is 216t + 30.

Hence, the correct option is B. t(12 x 18) + 30.

To find the total charge for a membership for t years, we need to calculate the monthly maintenance fee for t years and add it to the one-time registration fee.

The monthly maintenance fee for t years would be $18 multiplied by the number of months in t years, which is 12t.

So, the monthly maintenance fee for t years is 12t x $18.

Adding the one-time registration fee of $30, the total charge for a membership for t years is t(12 x 18) + 30.

Therefore, the correct answer is B. t(12 x 18) + 30.