Answer:
the probability = 0.875
Step-by-step explanation:
We can find the probability that at least one of the tosses will land heads up by using the binomial distribution.
[tex]\boxed{P(x)=_nC_x\cdot p^x(1-p)^{n-x}}[/tex]
where:
Instead of adding the probabilities of 1 head, 2 heads and 3 heads. It will be easier to subtract the probability of 0 head with 1. Therefore:
[tex]P(\texttt{at least 1 head)}=1-P(0)[/tex]
Given:
[tex]\begin{aligned}\\P(\texttt{at least q head})&=1-P(0)\\\\&=1-_3C_0\cdot (0.5)^0(1-0.5)^{3-0}\\\\&=1-\frac{3!}{0!(3-0)!} (1)(0.5)^3\\\\&=\bf 0.875\end{aligned}[/tex]