please solve asap

A regular customer visits a restaurant thrice a week. For a monthly visit, he wants to try something new every time he has a meal. Menu offers variety of items to be chosen from. He devised a formula to calculate the menu number of next meal which is given by n 2 (n + 1)2 / 4. What would be his last meal of the month? Another way to calculate the menu number is 1 3 + 23 + 33 + n3 . Can you validate both methods for choice of menu? 12:38 pm t