The Math Club is ordering food to be delivered to their meeting. They have a coupon for $10 off their order, and each member contributes an additional $5 for the food. The expression 5n + 10 represents the total amount they can spend on their order. Why would it not make sense to substitute 12.125 for n in this expression? A n represents the number of members, so it must be a whole number. B 5n represents the number of members, so n must be a whole number. C n represents an amount of money, so it cannot have more than two decimal places. D 5n represents an amount of money, so n cannot have more than two decimal places.

Since 12.125 is a decimal, it would not make sense to substitute 12.125 for n in the expression. You cannot have 1/8 of a person. Since each member is contributing an additional $5, the expression will show n as the variable representing the number of members in the Math Club. Each member is giving 5, so 5n + 10, the 10 being the coupon they have for $10 off. This expression shows how much money the entire group has.