Question

Ruby has $0.86 worth of pennies and nickels. She has 4 more nickels than pennies. Determine the number of pennies and the number of nickels that Ruby has.

Answer 1

86 = 1p + 5n

n = p + 4

86 = 1p + 5(p + 4)

86 = 1p + 5p + 20

66 = 6p; p = 11

86 = 1(11) + 5n

86 = 11 + 5n

75 = 5n; 15 = n

11 pennies, 15 nickels

11(1) + 15(15) = 11 + 75 = 86