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Yakvenalex [24]

3 years ago

11

Javon spent %687 on pokemon cards. Energy cards cost $6 and dragon cards cost $5. If he bought a total of 127 packs then how man

y of each did he buy

1 answer:

pshichka [43]3 years ago

3 0

Answer:

Javon purchase Energy cards = 52

Javon purchase Dragon cards = 75

Step-by-step explanation:

Given - Javon spent $687 on pokemon cards. Energy cards cost $6

and dragon cards cost $5.

To find - If he bought a total of 127 packs then how many of each did he buy ?

Proof -

Let Javon purchase Energy cards = x

Javon purchase Dragon cards = y

Now,

Given that he bought a total of 127 packs

⇒x + y = 127

Also,

Cost for 1 Energy card = $6

⇒Cost of x Energy cards = $ 6x

And

Cost of 1 Dragon card = $5

⇒Cost of y Dragon card = $ 5y

Now,

Given that Javon spent $687 on pokemon cards.

⇒6x + 5y = 687

∴ we get

x + y = 127 ..................(1)

6x + 5y = 687 .................(2)

Multiply by 6 in equation (1) , we get

6(x + y) = 6(127)

⇒6x + 6y = 762 .................(3)

Now,

Subtract equation (2) from equation (1) , we get

6x + 6y - (6x + 5y )= 762 - 687

⇒6x + 6y - 6x - 5y = 75

⇒y = 75

Now,

Put the value of y in equation (1), we get

x + 75 = 127

⇒x = 127 - 75

⇒x = 52

∴ we get

Javon purchase Energy cards = x = 52

Javon purchase Dragon cards = y = 75

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2 years ago

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monitta

Answer:

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Step-by-step explanation:

Let X the random variable of interest "number cleared by arrest or exceptional", on this case we can model this variable with this distribution:

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Part b

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$P(X=38)=(50C38)(0.65)^{38} (1-0.65)^{50-38}=0.0319$

And adding these values we got:

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Part c

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