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2 years ago

In one particular suburb, there are 5 families that own a boxer. If there are a total of

Mathematics

1 answer:

icang [17]2 years ago

3 0

Answer:

60%

Step-by-step explanation:

Explanation:

To get percentages, take the part of a population that is being specified and divided that by the whole population and multiply that value by

100

So there are

people that own boxers, this is the specific population that is being compared to the whole dog-owning population, which is comprised of

total families. So

can be reduced to

and that gives us

When that value is multiplied by

100

, it gives us our percentage of

⋅

100

You might be interested in

B. (x + 3)(x^2 – 3x + 27 )=

natali 33 [55]

(x+3)(x^2-3x+27)

x^3-3x^2+27x+3x^2-9x+81

x^3+19x+8

3 0

3 years ago

The cost to mall a package is $5 for the first 2 pounds and 40 cents for each additional ounce. Which of the following functions

erica [24]

Answer:

Step-by-step explanation:

5 times 2 equales 10 divided by 40 eqauls 4 times 2 equals 8

5 0

2 years ago

50 points! I understand A. and B. but I would really appreciate help with C.

FromTheMoon [43]

Answer:

$51.72\text{ cells per hour}$

Step-by-step explanation:

So, the function, P(t), represents the number of cells after t hours.

This means that the derivative, P'(t), represents the instantaneous rate of change (in cells per hour) at a certain point t.

So, we are given that the quadratic curve of the trend is the function:

$P(t)=6.10t^2-9.28t+16.43$

To find the <em>instanteous</em> rate of growth at t=5 hours, we must first differentiate the function. So, differentiate with respect to t:

$\frac{d}{dt}[P(t)]=\frac{d}{dt}[6.10t^2-9.28t+16.43]$

Expand:

$P'(t)=\frac{d}{dt}[6.10t^2]+\frac{d}{dt}[-9.28t]+\frac{d}{dt}[16.43]$

Move the constant to the front using the constant multiple rule. The derivative of a constant is 0. So:

$P'(t)=6.10\frac{d}{dt}[t^2]-9.28\frac{d}{dt}[t]$

Differentiate. Use the power rule:

$P'(t)=6.10(2t)-9.28(1)$

Simplify:

$P'(t)=12.20t-9.28$

So, to find the instantaneous rate of growth at t=5, substitute 5 into our differentiated function:

$P'(5)=12.20(5)-9.28$

Multiply:

$P'(5)=61-9.28$

Subtract:

$P'(5)=51.72$

This tells us that at <em>exactly</em> t=5, the rate of growth is 51.72 cells per hour.

And we're done!

7 0

2 years ago

A pole that is 3.4 m tall casts a shadow that is 1.54 m long. At the same time, a nearby building casts a shadow that is 35.75 m

inna [77]

Answer:

The building would be 78.92 meters tall.

Step-by-step explanation:

If the shodow of a 3.4m tall pole is 1.54m tall, and you have the shadow's height, then you make a cross, multiply-divide ratio table.

5 0

2 years ago

The manufacturer of hardness testing equipment uses steel-ball indenters to penetrate metal that is being tested. However, the

kumpel [21]

Answer:

Check the explanation

Step-by-step explanation:

Let X denotes steel ball and Y denotes diamond

$\bar{x_1}$ = 1/9( 50+57+......+51+53)

=530/9

=58.89

$\bar{x_2}$ = 1/9( 52+ 56+....+ 51+ 56)

=543/9

=60.33

difference = d =(60.33- 58.89)

=1.44

$s^2=1/n\sum xi^2 - n/(n-1)\bar{x}^2$

s12 = 1/9( 502+572+......+512+532) -9/8 (58.89)2

=31686/8 - 9/8( 3468.03)

=3960.75 - 3901.53

=59.22

s1 = 7.69

s22 = 1/9( 522+ 562+....+ 512+ 562) -9/8 (60.33)2

=33295/8 - 9/8 (3640.11)

=4161.875 - 4095.12

=66.75

s2 =8.17

sample standard deviation for difference is

s= $\sqrt{[(n1-1)s_1^2+ (n2-1)s_2^2]/(n1+n2-2)}$

= $\sqrt{[(9-1)*59.22+ (9-1)*66.75]/(9+9-2)}$

= $\sqrt{1007.76/16}$

=7.93

sd = $s*\sqrt{(1/n1)+(1/n2)}$

= $7.93*\sqrt{(1/9)+(1/9)}$

=7.93* 0.47

=3.74

For 95% confidence level $Z (\alpha /2)$ =1.96

confidence interval is

$d\pm Z(\alpha /2)*s_d$

=(1.44 - 1.96* 3.75 , 1.44+1.96* 3.75)

=(1.44 - 7.35 , 1.44 + 7.35)

=(-2.31, 8.79)

There is sufficient evidence to conclude that the two indenters produce different hardness readings.

3 0

3 years ago