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3 years ago

Why are all 4-digit Fredholl numbers composite?

1 answer:

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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Complete the function table.

Nesterboy [21]

Step-by-step explanation:

with the y= 4x +1

they find the first column by replacing x in the function by 0

meaning if x= 0 then y=4(0) + 1 so y=1

for the second column if x =2 then y= 4(2) +1 so y= 9

for the 3rd one if x =4 then y = 4(4)+1 so y = 17

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3 years ago

The mean temperature for the first 4 days in january was 1°C. The mean temperature of the first 5 days in January was 2°C. What

Lorico [155]

Answer:

Step-by-step explanation:

mean is average, so if we label the first through fifth days of january a-e we can solve it.

So average of the first four is (a+b+c+d)/4 = 1 and the first five is (a+b+c+d+e)/5 = 2. Since it's easy, let's get rid of the fraction in both.

(a+b+c+d)/4 = 1 and (a+b+c+d+e)/5 = 2

a+b+c+d = 4 and a+b+c+d+e = 10

Now, we know a+b+c+d is 4, so we can replace that in the second equation

a+b+c+d+e = 10

4 + e = 10

e = 6

ad since e is the fifth day, we know the temperature of it. Let me know if something here didn't make sense.

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3 years ago

Read 2 more answers

Remmi wrote the equation of the line y=1/3(x+2) He solved for x and got x=3y-2 Which of the following is an equivalent equation

gregori [183]

<span>the equation of the line y = 1/3 (x+2)
to solve for x , multiply the whole eqaution by 3, which results to:
</span>[y = 1/3 (x + 2)] 3
3y = x + 2
then transpose the 2 to the other side of the equation
3y - 2 = x
x = 3y - 2
so the answer of remmi is correct. i hope this can help you, feel free to ask for clarifications

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3 years ago

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kap26 [50]

Answer:0.35

Step-by-step explanation:

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3 years ago

If possible, please help me with this problem. I do not understand what method and such.

Ivenika [448]

Answer:

14 m^2

Step-by-step explanation:

The method used to find the area of this trapezoid is to put the given numbers into the formula for the area of a trapezoid. That formula is ...

A = (1/2)(b1 +b2)h

where b1 and b2 are the lengths of the parallel bases, and h is the perpendicular distance between them.

The figure shows you that b1 and b2 are 5 m and 2 m (in no particular order) and h is 4 m. Putting these numbers into the formula gives ...

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3 years ago