Question

Benson Automotive earned $69.46 interest on a $9,400 deposit in an account paying 4.5%. Find the number of days that the funds were on deposit. Round to the nearest whole dayLearning simple interest.

Answer 1

The rate given is 4.5%, but it didn't say theperiod of the intereset. In this case, we normally implies that the interest is annual.

The equation for simple interest is as follows:

$I=P\cdot r\cdot t$

Where P is the princiapal value, r is the rate and t is the time period in years, because the rate is annual.

We want to calculate t, so we can solve for it:

$t=\frac{I}{P\cdot r}$

Ans we substitute the values:

$t=\frac{69.46}{9400\cdot4.5\%}=\frac{69.46}{9400\cdot0.045}=0.164208\ldots$

That is, 0.164208... years.

In one normal year, we have 365 days, so the time in days is:

$0.164208\ldots\cdot365=59.935\ldots\approx60$

So, the answer is 60 days.