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3 years ago

If X and Y are random variables with E(X) = 6 and E(Y) = 9, then E(2X + 3Y) is: -39-15-27-12

Mathematics

1 answer:

a_sh-v [17]3 years ago

7 0

Expectation is linear in the sense that

$E[2X+3Y]=E[2X]+E[3Y]=2E[X]+3E[Y]$

so that

$E[2X+3Y]=2\cdot6+3\cdots9=12+27=\boxed{39}$

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at a certain real estate firm, realtor selling house recieve a comission:6% for the first 160,000 of the selling price, and 4% f

Natali [406]

Let the amount be x.

6% for the first 160000

= 6/100 * 160000 = 9600

4% for any amount exceeding 160000.

= 4/100 * (x -160000) = 0.04(x-160000)

The sum of both commission should be equal to 10560.

9600 + 0.04(x -160000) = 10560

0.04(x -160000) = 10560 - 9600

0.04(x -160000) = 960 Divide by 0.04.

(x -160000) = 960/0.04

(x -160000) = 24000

x = 24000 + 160000 = 184000.

Selling price = 184000

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3 years ago

I have 10 sweets. My brother ate 3 sweets and I ate 4. What fraction of my sweets did we eat altogether? (Think about: what is t

Gnom [1K]

Answer:

7/10

Step-by-step explanation:

If you have 10 sweets

Your brother eats 3

You eat 4

3 + 4 = 7

7 out of ten = 7/10

So therefore the answer is 7/10

7 0

3 years ago

Read 2 more answers

PLEASE HELP ME I AM FAILING. I WILL GIVE BRAINLIEST

den301095 [7]

Answer:

equation = $\sqrt{7^2 + 12^2 } = c$

Using:

$\sqrt{a^2 + b^2 } = c$ or $a^2 + b^2 = c^2$ or

7^2 + 12^2 = c^2

49 + 144 = c^2

c^2 = 193

missing length = 13.9 inches

4. equation = $\sqrt{24^2 + 32^2} = c$

Using:

$\sqrt{a^2 + b^2 } = c$ or $a^2 + b^2 = c^2$

24^2 + 32^2 = c^2

reduce to:

8 multiplied by everything:

3^2 + 4^2 = c^2

Since we know 3,4,5 is a Pythagorean triple, we can use this to find c.

Since c must be 5, we multiply by 8 since we divided by 8 earlier to get the 3,4,5 and get 40.

missing length = 40 inches

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3 years ago

A Biycle wheel has a diameter of 52cm.

schepotkina [342]

Answer:

26cm

Step-by-step explanation:

because 2 radius equal 1 diameter

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3 years ago

Given that X={whole numbers less than 24}

hodyreva [135]

Step-by-step explanation:

X= {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23}

P= {2,3,5,7,11,13,17,19,23}

Q= {2,4,6,8,10,12,14,16,18,20,22}

a= {2,3,4,5,6,7,8,10,11,12,13,14,16,17,18,19,20,22,23}

b= {2,}

c= we first find p'

p'={1,4,6,8,9,10,12,14,15,16,18,20,21,22}

c={4,6,8,10,12,14,16,18,20,22}

d=we do same here but we already have p' so we find for q'

q'={1,4,6,8,9,10,12,14,15,16,18,20,21,22}

d={1,4,6,8,9,10,12,14,15,16,18,20,21,22}

6 0

3 years ago