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2 years ago

5

Why are all 4-digit Fredholl numbers composite?

1 answer:

GaryK [48]2 years ago

6 0

Fredholl numbers are number, which have 2 different digits, equal number of each one, and zero cannot be the first digit. Some examples of fredholl numbers are: 355533 and 4141.
233233, 535351 or 055050 are not fredholl numbers.

In case of 4 digit numbers let's look at the possible forms of Fredholl numbers:

They have to be one of the following: xxyy, xyxy, xyyx
We can write above numbers as:
$xxyy= x*1100 + y*11 = x*11*100 + y*11 = 11 (100x+y) xyxy= x*1010 + y*101 = x*101*10 + y*101 = 101 (10x+y) xyyx=x*1001 + y*110 = x*11*91 + y*11*10 = 11 (91x+10y)$

All 4-digit Fredholl numbers are composite because they will be divisible by either 11 or 101.

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2 years ago

27^x = 9^x − 4 Question 1 options: x = 8 x = 4 x = −4 x = −8

Mariulka [41]

Answer:

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Step-by-step explanation:

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3 years ago

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2 years ago

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2 years ago

You could win a giant jar of M&Ms, if only you could guess how many are in the jar. You find a smallerjar such that the gian

sleet_krkn [62]

Answer:

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Step-by-step explanation:

We are given the following in the question:

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2 years ago