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

Answer:
-24
Step-by-step explanation:
They get 2/3 because 2 divided by 3=2/3.
Answer:
access to safe drinking water is a fundamental need and human right. Securing access for all would go a long way in reducing illness and death, especially among children. “Safely managed” drinking water services represent an ambitious new rung on the ladder used to track progress on drinking water. Since 2000, 2 billion people have gained access to safely managed services (i.e., accessible on-premises, available when needed, and free from contamination). In 2020, 5.8 billion people used safely managed services and a further 2 billion people used basic services ( improved sources within 30 minutes per round trip to collect water).
However, 771 million people still lacked even a basic level of service, including 282 who used a “limited” water service (improved source from which water collection exceeds 30 minutes), 367 million who used unimproved sources and 122 million who still collected drinking water directly from rivers, lakes, and other surface water sources. The data reveal pronounced disparities, with the poorest and those living in rural areas least likely to use a basic service. In most countries, the burden of water collection continues to fall mainly to women and girls.
Step-by-step explanation:
Sorry :(