# by defining our variables

A comprehensive investment plan is made for a person with a total investment of $26,300. The money is broken into three investments. Part of the money is invested into a retirement account 5.1% interest per year, part is invested in a saving account earning 2.8% interest per year, and part is invested into a certificate of deposit earning 3.0% interest per year. The goal is to earn $1133.60 in interest at the end of one year. One last piece of information is that the broker recommends that you invest twice as much into savings as you do into the certificate of deposit. How much money went into each account?

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#### Solution Preview

Lets start by defining our variables:

x: Amount invested in retirement account

y: Amount invested in savings account

z: Amount invested in certificate of deposit

We know that the total invested is $26,300 so:

x + y + z = 26300

We also know that the interest on each account is as follows:

x: 5.1% = 0.051

y: 2.8% = 0.028

z: 3% = 0.03

Additionally we know that the total interest desired is 1133.60 giving us:

0.051x + 0.028y + 0.03z = ...

#### Solution Summary

The total interest desired is articulated in the following posting.