If the productivity of a brigade grows by 5% when the number of the workers in the brigade is increased by one, then which of the following is closest to the ratio of the productivity of a 12-person brigade to that of a 10-person brigade?  Choices.
A) 0.21
B) 0.82
C) 1.155
D) 1.21
E) 1.44
B = 10-men brigade   p = increase in the productivity = 5%   Solution: B x p = B x 1.05 = 1.05B -------&gt; the productivity of 11 men brigade   1.05B x p = 1.05B x 1.1 = 1.155B -----&gt; the productivity of 12 men brigade   The ratio of the productivity of a 12-men brigade to that of a 10-men brigade = 1.155B/B = 1.155   1.155
<result>C</result>
If the productivity of a brigade grows by 5% when the number of the workers in the brigade is increased by one, then which of the following is closest to the ratio of the productivity of a 12-person brigade to that of a 10-person brigade?