Question

The library at a certain university reported that journal prices had increased by 130% over a period of 10 years. The report concluded that this represented a price increase of 13% each year. If journal prices had indeed increased by 13% each year, what percentage increase would that give over 10 years? (Round your answer as a percentage to the nearest whole number.)

Answer 1

300%

Explanation:

Here we have an exponential function,
`y=ab^x`and it is one of the most important functions in the mathematics. In this case, the independet variable is the exponent.

Here we have that represented price increase of 13% each year, which means that
`b=1.13>1` in our exponential function, while
`a` represent the journal price at the begining.

So we get the following function:

`y=a(1.13)^x,\\`

where
`x` represents number of years. After 10 years, we get:

`y=a(1.13)^(10)=3.395a`

The conclusion is that over 10 years, the percentage of increase would be about 300%.