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defon
3 years ago
10

The difference of two numbers, a and b, is 21. The difference of 5 times a and two times b is 18. What are the values of a and b

?
A. 

4, 1

B. 

-19, 40

C. 

20, 1

D. 

30, 9

E. 

-8, -29
Mathematics
1 answer:
zheka24 [161]3 years ago
5 0

Answer:

E.  -8, -29

Step-by-step explanation:

a-b=21

5a -2b =18

Take the first equation and solve for a by adding b to each side

a-b=21

a-b+b=21+b

a = 21+b

Now substitute a=21+b into the second equation

5a -2b =18

5(21+b) -2b =18

Distribute the 5

105 +5b-2b =18

Combine like terms

105 +3b =18

Subtract 105 from each side

105-105 +3b = 18-105

3b = -87

Divide each side by 3

3b/3 =-87/3

b = -29

if b = -29, we can substitute it into a =21+b

a = 21-29

a = -8

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3 years ago
An apartment complex rents an average of 2.3 new units per week. If the number of apartment rented each week Poisson distributed
masya89 [10]

Answer:

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Step-by-step explanation:

Given

Poisson Distribution;

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Required

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<em />

Using probability notations;

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P(X = 0) = \frac{2.3^0 * e^{-2.3}}{0!}

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P(X\leq 1) = 0.33085418427

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6 0
3 years ago
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Aleks04 [339]

Answer:

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8 0
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