Helmet

Nowadays, better results can be obtained in cycling due to the rider's physical preparation and updated technologies. One of the essential parts of the rider's equipment is their helmet.
While most bikers wear a helmet mainly to protect themselves, racers use modern technologies, which can improve certain features like aerodynamics and, in this way, enable them to reach a better time in a race. It's pretty essential, especially during the time trial part of the race.

Providing the helmet thanks to its advanced shape can increase the racer's performance by a half percent. HOW MUCH can the racer shorten the time in a 40-minute time trial?

Correct answer:

t =  12 s

Step-by-step explanation:

$$\begin{gathered} p=\frac{0.5}{100}=\frac{1}{200}=0.005 \\ {t}_1=40\text{min}\to \text{s}=40\cdot 60\text{s}=2400\text{s} \\ t=p\cdot t_1=\frac{1}{200}\cdot 2400=\frac{1\cdot 2400}{200}=\frac{2400}{200}=12\text{s} \end{gathered}$$

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