Answer:
\mu = 14.5\\
\sigma = 5.071\\
k = 1.084
Step-by-step explanation:
given that a statistician uses Chebyshev's Theorem to estimate that at least 15 % of a population lies between the values 9 and 20.
i.e. his findings with respect to probability are

Recall Chebyshev's inequality that

Comparing with the Ii equation which is appropriate here we find that

Next what we find is

Thus from the given information we find that

it is cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
Answer: $18.51
Step-by-step explanation:
She paid $50
Her total purchases
$9.99 + $21.50 = 31.49
Change = (50 - 31.49) = 18.51
2/3, 12/18, and 24/36 should be okay.