Double probability

The probability of success of the planned action is 60%. What is the probability that we will achieve success at least once if this action is repeated twice?

Correct answer:

p =  0.84

Step-by-step explanation:

$$\begin{gathered} p_1=60\mathrm{\%}={\displaystyle \frac{60}{100}}=0.6 \\ p=p_1+p_1-p_1\cdot p_1=0.6+0.6-0.6\cdot 0.6={\displaystyle \frac{21}{25}}=0.84 \end{gathered}$$

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