Question

$8$ unbiased coins are tossed at a time $512$ times.The expected frequency of getting one head is

• A. $4$
• B. $8$
• C. $16$
• D. $20$

Answer 1

The correct option is C $16$

The probability of one head, when 8 unbiased coins are tossed.
${}^8{C}_1\left(\frac{1}{2}{)}^1\right(\frac{1}{2}{)}^7$
$=\frac{8}{256}$
Hence the expected frequency is
$=512\left(\frac{8}{256}\right)$
$=2\left(8\right)$
$=16$