Carcass wrote:

Explanation

Let k be Jack’s annual salary in 2011, and let r be Arnie’s annual salary in 2011. Then Jack’s annual salary in 2012 was 1.1k, and Arnie’s was 0.95r. Since their salaries in 2012 were equal to each other, you have 0.95r = 1.1k. Solving the equation for r, you get r = \frac{1.1}{0.95} * k

Since \frac{1.1}{0.95} = 1.1578 it follows that, rounded to the nearest 0.1%, Arnie’s annual salary in 2011 was 15.8% greater than Jack’s annual salary in 2011.

The correct answer is 15.8.

for the above answer, I don't think it is calculated properly according to question. I the question there is percentage increase asked. here its merely the number of times the salary is more is calculated