The test

The test contains four questions, and there are five different answers to each of them, of which only one is correct, the others are incorrect. What is the probability that a student who does not know the answer to any question will guess the right answers to all the questions?

Correct result:

p =  0.16 %

Solution:

$$\begin{gathered} q=1\mathrm{/}5={\displaystyle \frac{1}{5}}=0.2 \\ n=4 \\ p=100\cdot q^n=100\cdot 0.2^4={\displaystyle \frac{4}{25}}={\displaystyle \frac{4}{25}}\mathrm{\%}=0.16\mathrm{\%} \end{gathered}$$

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Math student

You make it simple where I can understand thank you so much

5 months ago  Like

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