A teacher randomly selects three students each month from a class of 30 students to be the students of the month. Each student receives a special certificate special seating in class, and a free homework pass. How many different groups of three students could be selected?

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?