7. Official UK accident statistics showed that there were 225 accidents involving teapots in one year. However, in the following year there were 47 such accidents.
What was the approximate percentage reduction in recorded accidents involving teapots from the first year to the second?
A 50
B 60
С 70
D 80
E 90
Solution
D
The reduction in the number of teapot accidents in the second year was $225-47=178$. 178 as a percentage of 225 is
$$
\frac{178}{225} \times 100 \approx \frac{180}{225} \times 100=\frac{20}{25} \times 100=20 \times 4=80 \text {. }
$$