A nation had a birth rate of 20 in 1990.The rate fell to 13 in 2000.What was the percentage change?
A) $\left( \frac { 20 - 13 } { 20 } \right) \times 100 = 35 \%$
B) $\left( \frac { 20 - 13 } { 13 } \right) \times 100 = 54 \%$
C) $\left( \frac { 13 - 20 } { 20 } \right) \times 100 = - 35 \%$
D) $\left( \frac { 13 - 20 } { 13 } \right) \times 100 = - 54 \%$

Question

Quizplus · Accepted Answer

To find the percentage change, we use the formula:

$$\text{Percentage Change} = \left(\frac{\text{New Value} - \text{Old Value}}{\text{Old Value}}\right) \times 100 \%$$

In this case, the old value is the birth rate in 1990, which is 20, and the new value is the birth rate in 2000, which is 13. Substituting these values into the formula, we get:

$$\text{Percentage Change} = \left(\frac{13-20}{20}\right) \times 100 \%$$

Simplifying, we get:

$$\text{Percentage Change} = -35\% $$

So the answer is C, which corresponds to -35%.

A Nation Had a Birth Rate of 20 in 1990 (20−1320)×100=35%\left( \frac { 20 - 13 } { 20 } \right) \times 100 = 35 \%(2020−13​)×100=35%

A Nation Had a Birth Rate of 20 in 1990 $\left( \frac { 20 - 13 } { 20 } \right) \times 100 = 35 \%$