A fair coin

A fair coin is tossed twice. Write down the set of possible outcomes.
What is the probability of obtaining it?
I. Exactly one head
ii. No head

Correct answer:

p₁ =  0.5
p₂ =  0.25

Step-by-step explanation:

$$\begin{gathered} HH \\ HT \\ TH \\ TT \\ {p}_1=\frac{2}{4}=\frac{1}{2}=0.5 \end{gathered}$$

$p_2=\frac{1}{4}=0.25$

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