A study investigates the effectiveness of a new safety helmet for cyclists. Out of 18001800 cyclists not wearing the new helmet, 2727 suffered serious head injuries. Out of 54005400 cyclists wearing the new helmet, 99 suffered serious head injuries. At the 0.050.05 significance level, test the claim that the new helmet reduces the risk of serious head injury. What does the result suggest about the effectiveness of bicycle helmets?

The result suggests that the new helmet is effective in reducing serious head injuries for cyclists at the 0.050.05 significance level.

The result suggests that the new helmet is not effective in reducing serious head injuries for cyclists at the 0.050.05 significance level.

A study investigates the effectiveness of a new safety helmet for...

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