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) 30% decrease

Explanation:

We proceed with the calculation as follows:

For September 1, 1992

For simplicity purpose, let us assume the total number of construction workers in 1992 is 100.

Since, construction workers’ unemployment rate in 1992 = 16%

Therefore;

Number of unemployed construction workers in 1992 = 16

For September 1, 1996

Since the number of construction workers was 20 percent greater on September 1, 1996, than on September 1, 1992, we have:

Total number of construction workers in 1996 = 100 × (1 + 0.2) = 120

Since, construction workers’ unemployment rate in 1996 = 9%

Therefore;

Number of unemployed construction workers in 1996 = 120 × 9% = 10.8

Calculation of change in the number of unemployed construction workers between September 1, 1992 and September 1, 1996

Change in number of unemployed construction workers = 10.8 - 16 = – 5.2

This implies a decrease of 5.2. This will be used is absolute term to calculate the percentage as follows:

Percentage of Change number of unemployed construction workers = (5.2 ÷ 16) × 100 = 32.5% decrease

Since 32.5% is approximately 30% which is the closest in the question, the approximate percentage change in the number of unemployed construction workers between September 1, 1992 and September 1, 1996 is therefore a 30% decrease.

Note:

In real life, there cannot be 10.8 or 5.2 unemployed construction workers. We just used the figures as a hypothetical example without rounding to get for simplicity purpose.