The greatest one-year growth was between 98 and 99. Several options include this period, but since the other periods had lower growth, the AVERAGE growth for the longer time periods is smaller. Therefore the answer is D.

sanju09 wrote:The bar graph attached shows the number of employees at Company X for each of the years from 1996 through 2000. Over which of the following periods was the average rate of increase in the number of employees at Company X greatest?

(A) From 1996 through 1998
(B) From 1996 through 1999
(C) From 1997 through 1999
(D) From 1998 through 1999
(E) From 1998 through 2000

E is a garbage answer, throw it out.
A doesn't include the greatest spike in employees throw it out

BCD are left
The greatest rate of increase would be for the smallest amount of time that includes the 1999 year.

Greatest rate of increase must be D.

Please start posting the OA

Im a bit confused on these questions. Are we supposed to guesstimate where the graph lies on the Y axis, or just assume that its in the middle?

You can estimate the rate of increase for each of the five choices to find which is the greatest.

From 1996 through 1998, Company X gained roughly 20 employees over 2 years, for an average rate of increase of about 10 employees per year.

From 1996 through 1999, Company X gained roughly 75 employees over 3 years, for an average rate of increase of about 25 employees per year.

From 1997 through 1999, Company X gained roughly 65 employees over 2 years, for an average rate of increase of about 32 employees per year.

From 1998 through 1999, Company X gained roughly 55 employees over 1 year, for a rate of increase of about 55 employees per year.

From 1998 through 2000, Company X gained roughly 30 employees over 2 years, for an average rate of increase of about 15 employees per year.

Of the choices, the average rate of increase in the number of employees at Company X was greatest for the period from 1998 through 1999.

There is also a quicker way to figure out the answer. Choice [spoiler](D)[/spoiler], from 1998 through 1999, is the single largest yearly increase in the number of employees. Therefore, the average rate of increase for any other time period must be less than that for this 1-year period.