Question

If two coins are tossed 5 times, the chance that there will be 5 heads and 5 tails is

• A. $\frac{45}{256}$
• B. $\frac{120}{256}$
• C. $\frac{63}{256}$
• D. $\frac{30}{256}$

Answer 1

Answer: (C)

$\frac{63}{256}$

The cases when there will be 5 heads and 5 tails: H H H H H T T T T T
We could permute this case in $\frac{10!}{5!\times 5!}=252$ ways
Total cases when two coins are tossed for 5 time$=2^{10}=1024$
Chance that there will be 5 heads and 5 tails is$=\frac{252}{1024}=\frac{63}{256}$