How to work this out in geometry form?

At least two people have the same birthday in a school of 150 students

Pls i’m dumb as heck i’ll give y’all so many points if that encourages you

Carl wants to buy a television that cost $500 including taxes. to pay for television he will use a payment plan that requires him to make a down payment of $125 and then pay $70.50 each month for six months what is the percent increase from the original cast of the television to the cost of the television using a payment plan.