Let a Be the Set of All Strings of Decimal

question 55

Short Answer

let A be the set of all strings of decimal digits of length five. For example, 00312 and 19483
are strings in A.
-How many strings in A have exactly one 5?

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Definitions:

Deregulation

The act of eliminating governmental controls and rules in a sector to promote increased competition and efficiency.

Regulation

Rules or directives made and maintained by an authority to control or manage activities, often within industry sectors, for public good.

Allocative Efficiency

A state of the economy where the distribution of resources among different uses is optimal, with no one able to be made better off without making someone else worse off.

Marginal Benefits

The bonus satisfaction or utility acquired from consuming an additional unit of a product or service.