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2 years ago

If (a^3+27)=(a+3)(a^2+ma+9) then m equals

Mathematics

1 answer:

Ronch [10]2 years ago

7 0

Answer:

m = - 3

Step-by-step explanation:

a³ + 27 ← is a sum of cubes and factors in general as

a³ + b³ = (a + b)(a² - ab + b²), thus

a³ + 27

= a³ + 3³

= (a + 3)(a² - 3a + 9)

comparing a² - 3a + 9 to a² + ma + 9, then

m = - 3

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Five data entry operators work at the data processing department of the Birmingham Bank. Each day for 30 days, the number of de

Mice21 [21]

Answer:

Step-by-step explanation:

p = Total Number of Defects / Sample Size x Number of Samples

302 / 300 x 30 = 0.0336

z = Number of standard deviation = 3

σ = Standard deviation of sampling distribution

σ = p (1- p) / n = 0.0336 (1- 0.0336) / 300 = 0.0336 x 0.9664 / 300 = 0.0104

Here, n = number of observations in each sample

UCL = p+zσ = 0.0336 + 3(0.0104) = 0.0336 + 0.0312 = 0.0648 = 0.065

LCL = p-zσ = 0.0336 - 0.0312 = 0.0024 = 0.002

b) Hence, Lower control limit cannot be a negative number as percent defective cannot be a negative number. As such, No. Percent of defective records cannot be a negative number.

7 0

2 years ago

The lifespans of lions in a particular zoo are normally distributed. The average lion lives 12.512.512, point, 5 years; the stan

zaharov [31]

This question was not written properly

Complete Question

The lifespans of lions in a particular zoo are normally distributed. The average lion lives 12.5 years; the standard deviation is 2.4 years. Use the empirical rule (68-95-99.7\%)(68−95−99.7%) to estimate the probability of a lion living between 5.3 to 10. 1 years.

Answer:

Thehe probability of a lion living between 5.3 to 10. 1 years is 0.1585

Step-by-step explanation:

The empirical rule formula states that:

1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.

2) 95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ.

3) 99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.

Mean is given in the question as: 12.5

Standard deviation : 2.4 years

We start by applying the first rule

1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.

μ - σ

12.5 -2.4

= 10.1

We apply the second rule

2) 95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ.

μ – 2σ

12.5 - 2 × 2.4

12.5 - 4.8

= 7.7

We apply the third rule

3)99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.

μ - 3σ

= 12.5 - 3(2.4)

= 12.5 - 7.2

= 5.3

From the above calculation , we can see that

5.3 years corresponds to one side of 99.7%

Hence,

100 - 99.7%/2 = 0.3%/2

= 0.15%

And 10.1 years corresponds to one side of 68%

Hence

100 - 68%/2 = 32%/2 = 16%

So,the percentage of a lion living between 5.3 to 10. 1 years is calculated as 16% - 0.15%

= 15.85%

Therefore, the probability of a lion living between 5.3 to 10. 1 years

is converted to decimal =

= 15.85/ 100

= 0.1585

8 0

2 years ago

NEED HELP ON NUMBER 13 AND 14

Kazeer [188]

Answer:

Question 13: For age groups y=1 and y=1.3 response is 8 microseconds.

Question 14: The club was making a loss between 11.28 and 4.88 years.

Step-by-step explanation:

Question 13:

The age group y for which the response rate R is 8 microseconds is given by the solution of the equation

$8=y^4 +2y^3 - 4y^2 -5y +14.$

We graph this equation and find the solutions to be

$y=1;$ $y=1.302;$ $y=-2;$ $y=-2.302.$

Since only positive solutions for y are valid in the real world we take only those.

Thus only for age groups y=1 and y=1.3 the response is 8 microseconds.

Question 14:

The footbal club is making a loss when $p(t)$

$t^3 -14t^2 +20t +120$

We graph this inequality and find the solutions to be

$t$ and $4.88$

Since in the real world only positive values for t are valid, we take the the second solution to be true.

Thus the club was making a loss in years $4.88$

5 0

2 years ago

A jet flying at 123 m/s banks to make a horizontal circular turn. The radius of the turn is 3810 m, and the mass of the jet is 2

aev [14]

Answer:

The magnitude of the necessary lifting force is 7.95N

Step-by-step explanation:

Force = mv^2/r

mass (m) = 2.00105kg, velocity (v) = 123m/s, radius (r) = 3810m

Force = 2.00105×123^2/3810 = 30273.89/3810 = 7.95N

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2 years ago

The ice cream Palace received 3 gallons of strawberry ice cream, 5 pints of mocha ice cream, and 1 quart of vanilla ice cream to

Alina [70]

They recived 31 pints of ice cream

6 0

2 years ago