Problema Solution
Bill has 39 coins consisting of nickels, dimes, and quarters. He has twice as many dimes as nickels and the number of quarters is one less that the number of dimes. How many quarters does he have?
Answer provided by our tutors
1 nickel = 5 cents
1 dime = 10 cents
1 quarter = 25 cents
let
n = the number of nickels, n is integer, n>=0
d = the number of dimes, d is integer, d>=0
q = the number of quarters, q is integer, q>=0
Bill has 39 coins consisting of nickels, dimes, and quarters
n + d + q = 39
he has twice as many dimes as nickels
d = 2n
the number of quarters is one less that the number of dimes
q = d - 1
by solving the system of equations
n + d + q = 39
d = 2n
q = d - 1
we find
n = 8 nickles
d = 16 dimes
q = 15 quarters
click here to see the step by step solution of the system of equations