安安老師在網路購買一套百
科全書,網路購書優惠全面
八折,優惠後價格為2580
元,百科全書原價是幾元?​

You have 6 dollars +12 pennies +to quarters + 4 dimes=2 nickels how much do you have

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

What expression is equivalent to 42x-56y