alexander had some nickles in his bank. he added 3 dimes to the bank and then he had 85 cents.how many nickles did he have left? write an equation and work backward to solve.
.05(x)+ .10(3)=.85
.05x+ .3=.85
-.3 -.3
.05x=.55
/.05 /.05
x=11
To solve this problem, let's work backward from the given information. Let's start by denoting the number of nickels Alexander had initially as "n." We are asked to determine how many nickels he had left, so let's call the number of nickels left "x."
We know that Alexander added 3 dimes to the bank, which means he had 3 x 10 = 30 cents from the dimes.
To find out how many nickels Alexander had left, we need to subtract the value of the dimes from the total amount in the bank. We are given that the total amount in the bank is 85 cents.
Therefore, we can write the equation: n - 30 = x.
By rearranging the equation, we have: n = x + 30.
Now, we are ready to substitute the value of "n" into the equation using the information given.
Since Alexander had a total of 85 cents in the bank, we can write another equation: 5n + 10(3) = 85.
By simplifying the equation: 5n + 30 = 85.
Now, let's isolate "n" by subtracting 30 from both sides of the equation: 5n = 85 - 30, which simplifies to 5n = 55.
Finally, divide both sides of the equation by 5: n = 55 / 5, resulting in n = 11.
Therefore, Alexander originally had 11 nickels in his bank.