Elementary Algebra Problem About Nickels and Pennies The question is:
When the piggy bank was opened, it yielded $5.22 in nickels and pennies. If there were 162 nickels and pennies altogether, how many of each were in the bank?
 A: "How many of each..." actually gives a hint about how to go about solving this. We have two things that we don't know: P, the number of pennies, and N, the number of nickels. 
You are probably learning systems of equations, so I'll take that approach. 
You need two equations. One will simply be the number of total coins:
N + P = 162. (They gave you this!)

Then there will be an equation about the value of the coins. I'm going to write this in cents.
The total amount of cents is 522 (given), which comes from 5 cents per nickel and 1 cent per penny. In other words, 
5N + 1P = 522.
I suggest elimination. Reply if you still need help...
A: You can either use explicit elimination as suggested, or implicitly as follows. If the bank contained $\:162\:$ pennies and $\:0\:$ nickels then the total amount would be $\:\$1.62\:$, which is $\:\$3.60\:$ short of $\:\$5.22\:.\:$ Exchanging a penny for a nickel adds $\:\$0.04\:,\:$ so we need to make $\ 3.6/0.04 = 360/4\ $ exchanges.
A: What have you tried?  Hint:  If you have $n$ nickels and $p$ pennies, how much money do you have?
A: 90 nickels and 72 pennies =162 coins and $5.22
