In a certain year, the difference between Mary’s and Jim’s annual salaries was twice the difference between Mary’s and Kate’s annual salaries. If Mary’s annual salary was the highest of the 3 people, what was the average (arithmetic mean) annual salary of the 3 people that year?

Answer: Average annual salary of the 3 people is equal to Kate's annual salary.Step-by-step explanation:Since we have given that Difference between Mary's and Jim's annual salaries be m-jDifference between Mary's and Kate's annual salaries be m-kAccording to question, we get that [tex]m-j=2(m-k)\\\\m-j=2m-2k\\\\2k-j=2m\\\\2k-j=m[/tex]Average annual salary of the 3 people would be [tex]\dfrac{m+k+j}{3}\\\\=\dfrac{2k-j+j+k}{3}\\\\=\dfrac{3k}{3}\\\\=k[/tex]Hence, average annual salary of the 3 people is equal to Kate's annual salary.