12. The volume of a square room has a door of 2m x 1.5m and two windows, each of 1m x 15m is 900m If the cost of paving tiles including wage at Rs. 7.50/m² is
Rs. 1687.50, find the cost of colouring 4 walls at Rs. 12.50/m?

15. jiovanni is looking in to two different companies that offer study guides for math exams.test prep 101 charges a $5 flat fee and an additional $0.25 per problem.math charges a $2 flat fee and an additional $0.50 per problem.how many prablems would make the costs of the two companies be equal? varibles: equations/eniqualities{ {