Problema Solution
the total value of nickles and dimes in a coin bank is $5.00 if the nickles were dimes and the dimes were nickles the total value of coins would be $4.00 find the number of nickles and the number of dimes in the bank
Answer provided by our tutors
$5.00 = 500 cents
$4.00 = 400 cents
so,
5n + 10d = 500
10n + 5d = 400
multiply the first equation by 2 and subtract the second equation:
(10n-10n) + (20d-5d) = 1000-400
15d = 600
d = 600/15 = 40
there are 40 dimes
5n + 10*40 = 500
5n = 100
n = 100/5 = 20
There are 40 dimes and 20 nickels