Question

spiral review

1. in 1969, the annual global mean temperature was 14°c. in 2019, the annual global mean temperature was 14.8°c. two different news websites reported this change.

website a
\in the last 50 years, the annual global mean temperature has increased by almost 6%.\
website b
\there has been an increase in the annual global mean temperature of approximately 5% during the last half century.\
which website more accurately reported the change? explain your thinking.

Explanation:

Step1: Calculate the percentage increase

The formula for percentage increase is \(\frac{\text{New Value}-\text{Old Value}}{\text{Old Value}}\times100\%\).
Here, the old value (in 1969) is \(14^{\circ}C\) and the new value (in 2019) is \(14.8^{\circ}C\).
So, \(\frac{14.8 - 14}{14}\times100\%=\frac{0.8}{14}\times100\%\).

Step2: Simplify the expression

\(\frac{0.8}{14}\times100\%=\frac{80}{14}\% \approx 5.71\%\).

Answer:

Website A reported an increase of almost \(6\%\) and Website B reported an increase of approximately \(5\%\). Since the actual percentage increase is approximately \(5.71\%\), Website A more accurately reported the change.