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1 year ago

A security alarm requires a four-digit code. The code can use the digits 0–9 and the digits cannot be repeated.

Mathematics

2 answers:

never [62]1 year ago

7 0

Answer:

The answer is C

Explanation: Given:A security alarm requires a four-digit code. The code can use the digits 0–9 and the digits cannot be repeated.

there is only 2 numbers which are greater than 7 i.e. 8 and 9. ∴ there is 2 possibility for first place.

For the remaining 3 digits there is 9 possibilities (including 1 which would left after choosing 1 from first place )

No of ways for the alarm code beginning with a number greater than 7= 2 P 1 x 9 P 3

Total ways of code with 4 digits= 10 P 4. Hope this helps :)

Oduvanchick [21]1 year ago

7 0

Answer: The answer is C

Step-by-step explanation:

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Answer:

$16\ acres$

Step-by-step explanation:

we know that

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In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin

Let

x ----> the number of acres

y ---> total operating costs

we have the ordered pair (20,551,520)

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Find the value of the constant of proportionality k

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substitute the values of x and y

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The linear equation is equal to

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2 years ago

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erica is making necklaces and bracelets to se at the craft show. it takes her 3 hours to make a necklace and 2 hours to make a b

bagirrra123 [75]

Answer:

Erica should make at least 10 necklaces and 15 bracelets to maximize her profit of P = (18 x + 15 y)

Step-by-step explanation:

Let the number of necklaces made = x

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Now, the time taken to make each necklace = 3 hrs

⇒The time taken to make x necklaces = x times 3 hours = 3x

Also, the time taken to make each bracelet = 2 hrs

⇒The time taken to make y necklaces = y times 2 hours = 2y

So, total time taken to make x necklace and y bracelets = 3x + 2y

Now selling cost of 1 necklace = $18

Also, selling cost of 1 bracelet = $15

So, total selling price of x necklace and y bracelets = 18 x + 15 y

So according to the question:

x + y = 25 ..... (1)

3x + 2y = 60 .... (2)

Solving the above system substitute y = 25- x in (1)

we get: 3x + 2y = 60 ⇒ 3x + 2(25 -x) = 60

or, x = 10

⇒ y = 25 - x = 25 - 10 = 15, or y = 15

So, she should make at least 10 necklaces and 15 bracelets to maximize her profit of P = (18 x + 15 y)

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1 year ago

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Which are linear pairs? Check all that apply.

boyakko [2]

Answer:

Options B, C and D

Step-by-step explanation:

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In other words, pair of supplementary angles is the linear pair.

From the figure attached,

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2). ∠BAE and ∠EAD

3). ∠EAD and ∠DAC

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Answer:

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Step-by-step explanation:

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