Two numbers have a difference of 13. The sum of twice one number and 3 times the other number is 1.

Mr and mrs smith buy tickets for themselves and their four children. the cost of an adult ticket is ? 6 more than the adult ticket. the total cost of the six tickets is ? 40.50 work out the cost of an adult ticket. in your working let c be the cost of the child ticket and a be the cost of the adult ticket.

1) you deposit $2,500 in an account that earns 4% simple interest. how much do you earn in eight years?

What is r i 4.5+10r=-6.5 with work pls