Answer:
B's earning are 9% less than A's.
Explanation:
Let A and B represent the earning for A and B, respectively.
We learn that A = 1.1B ["A earns 10% more than B"]
Divide both sides by 1.1:
(A/1.1) = B
B = 0.909090909 or 0.91 to 2 sig figs
B's earning are (1-0.91 = 0.09) or 9% less than A's.