adam has 81 coins worth $5.75. all the coins are nickels and dimes. How many nickles does he have? How many dimes does he have?

Question

i really need help with this

Answer 1

Let d and n be the number of dimes and nickels.d + n = 81

10d + 5n = 575

10d + 5(81 - d) = 575

hence, d = 34  -->  n = 47

 

Answer 2

35 dimes would be 3.50

46nickels would be 2.25

 

Which together would equal 81 coins that equal $5.75