##### Algebra word problem

 Mathematics Tutor: None Selected Time limit: 1 Day

A child's coin bank contains \$1.42 in pennies and nickels.  If the number of pennies is 38 less than 4 times the number of nickels, how many pennies are in the bank?

Apr 28th, 2015

So we need to write some equations to solve for the amount of nickels and pennies, which represent our two variables. We know the total amount of nickels and pennies equals \$1.42, so we say 0.01P + 0.05N = 1.42. We also know the number of pennies is 38 less than 4 times the number of nickels, so we say P + 38 = 4N. So divide 4 from both sides to get N = 0.25P + 9.5. Plug that into the other equation to get 0.01P + 0.05(0.25P + 9.5) = 1.42. Distribute to get 0.01P + 0.0125P + 0.475 = 1.42. Subtract 0.475 and add the pennies together to get 0.0225P = 0.945. Divide 0.0225 from both sides and P = 42. So there are 42 pennies total in the coin bank.

Apr 28th, 2015

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Apr 28th, 2015
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Apr 28th, 2015
May 30th, 2017
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