How much invested in each type of investment? Define the variables. Kelly invested her savings of $4800. She invested part in mutual funds, at 9%/yr & the rest in GIC at 10%/yr. At end of year, the interest from mutual funds investment was $43 less than interest from GIC investment.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Let x be the amount invested in the mutual fund and let y be the amount invested in the GIC.  

Since the amount at the end of an investment period is `A=P(1+i)` , this means that the interest at the end of the investment period is I=Pi:

The amount of interest at the end of the year for the mutual fund is `I_M=x(0.09)=0.09x` .  The amount of interest at the end of the year for the GIC is `I_G=y(0.10)=0.1y` .

We also know that `x+y=4800` , so `y=4800-x` .  Since the interest from the mutual fund is $43 less than the interest from the GIC, then we can compare interest amounts to get:

`0.09x=0.1y-43` now sub in what we know 

`0.09x=0.1(4800-x)-43`   multiply by 100

`9x=48000-10x-4300`  move x to left side, simplify right side

`9x+10x=43700`  simplify

`19x=43700`    divide by 19


This means that `y=4800-2300=2500` .

The amount invested in mutual funds is $2300 and the amount in å GIC is $2500.

Approved by eNotes Editorial Team

Posted on

Soaring plane image

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial