In Country C, the unemployment rate among construction workers dropped from 16 percent on September 1, 1992, to 9 percent on September 1, 1996. If the number of construction workers was 20 percent greater on September 1, 1996, than on September 1, 1992, what was the approximate percent change in the number of unemployed construction workers over this period?

(A) 50% decrease (B) 30% decrease (C) 15% decrease (D) 30% increase (E) 55% increase

B is correct

Step-by-step explanation:

Let x be = number of in employed

Let y = number of labour force

X/Y = 0.16 = unemployment rate in 1991 ... equation 1

Increment of labour force by 20% in 1996 = 1.2y = number of labour force in 1996

Let c = number of unemployed in 1996

Unemployment rate in 1996 = c/1.2y =.09 ... equation 2

From equation 1

X =.16y ... equ3

From equation 2

C = 0.11y

To calculate approximately increase or decrease = [ (C - x) / x] * 100

So therefore;

[ (0.11y - 0.16y) / 0.16y] * 100 = - 31.25% approx = - 30 % decrease