Suppose that the scores on a statewide standardized test are normally distributed with a mean of 64 and a standard deviation of 2. Estimate the percentage of scores that were (a) between 60 and 68.

Answer:

q = 1/4

Step-by-step explanation:

-5/4 - (-1/4) = -1

-1/(q-1/2) = 4

-1 = 4(q-1/2)

-1 = 4q - 2

1 = 4q

q = 1/4

The question is incomplete. The complete question is :

In a survey of women in a certain country ( ages 20-29), the mean height was 62.9 inches with a standard deviation of 2.81 inches.  Answer the following questions about the specified normal distribution.  (a) What height represents the 99th percentile?  (b) What height represents the first quartile?  (Round to two decimal places as needed)

Solution :

Let the random variable X represents the height of women in a country.

Given :

X is normal with mean, μ = [tex]62.9[/tex] inches and the standard deviation, σ = [tex]2.81[/tex] inches

Let,

[tex]$Z=\frac{X - 62.9}{2.81}$[/tex] , then Z is a standard normal

a). Let the [tex]99th[/tex] percentile is = a

The point a is such that,

[tex]$P(X<a)=0.99$[/tex]

[tex]$P \left( Z < \frac{a-62.9}{2.81} \right) = 0.99$[/tex]

From standard table, we get : [tex]P( Z < 2.3263) =0.99[/tex]

∴ [tex]$\frac{(a-62.9)}{281} = 2.3263$[/tex]

  [tex]$a= (2.3263 \times 2.81 ) +62.9$[/tex]

     = 6.536903 + 62.9

     = 69.436903

     = 69.5 (rounding off)

Therefore, the height represents the [tex]99th[/tex] percentile = 69.5 inches.

b). Let b = height represents the first quartile.

It is given by :

[tex]P( X < b) =0.25[/tex]

[tex]$P \left( Z < \frac{(b-62.9)}{2.81} \right) = 0.25$[/tex]

From the standard normal table,

[tex]P( Z < -0.6745) =0.99[/tex]

∴ [tex]$\frac{(b-62.9)}{2.81}= 0.6745$[/tex]

[tex]$b=(0.6745 \times 2.81) +62.9$[/tex]

  = 1.895345 + 62.9

   = 64.795345

   = 64.8 (rounding off)

Therefore, the height represents the 1st quartile is 64.8 inches.

Answer:

Fraction form: x = -21/4

Decimal Form: x = -5.25

Step-by-step explanation:

See the picture for steps :)

Answer:

63,70

Step-by-step explanation:

7 x 8 = 56

7 x 11 = 77

multiples of 7 and 9, 7 x 10

63 and 70

7×9 = 63

7×10 = 70

Answered by Gauthmath must click thanks and mark brainliest

Answer:

-3

Step-by-step explanation:

Answer:

7/60

Step-by-step explanation:

Because the question is phrased such that it asks "the ratio of time with father to....", we know to put the time with father on top, or first. Similarly, since it is asked to put the ratio of time with the father to the time in daycare, we can put the daycare amount second/on the bottom. Therefore, we can write the ratio as

(42 minutes)/(6 hours)

To make both of these in terms of minutes to simplify it, we know that 60 minutes = 1 hour, so 1 hour / 60 minutes =1 . Since multiplying something by 1 keeps it the same, we can multiply our ratio by this amount. We want to multiply with the hour on top so the hours cancel out, as so:

[tex]\frac{42 minutes}{6 hours} * \frac{1 hour}{60 minutes} = \frac{42 minutes * hours}{360 minutes * hours} = \frac{42}{360}[/tex]

To simplify this even further, we can note that 6 is a factor of both 42 and 360*, so we can multiply this fraction by (1/6) / (1/6) to get

(42/360) * (1/6)/(1/6) = 7/60 as our final answer

If this doesn't come up immediately, you can always find the greatest common factor by listing the factors of each number and finding the highest one that fits both, e.g.

for 42: 42, 21, 14, 7 , 6...

for 360: 360,180, ... 6,5....

9514 1404 393

Answer:

  u = 7√2; v = 7

Step-by-step explanation:

The ratios of side lengths in an isosceles right triangle are ...

  1 : 1 : √2 = 7 : v : u

Then v = 7 and u = 7√2.

Answer:

9:15

girls : boys

Step-by-step explanation:

Answer:

9:15

Or 3:5 when reduced

Step-by-step explanation:

Answer: 7 miles/h and 1 miles/h

Step-by-step explanation:

With the speed of current = x + 1

Against the speed of current = x - 1

ATQ

4(x-1) = 3(x+1)

4x-4 = 3x+3

4x - 3x = 3+4

x = 7

Speed of boat = 7miles/h

Current of river = 1 miles/h

please click thanks and mark brainliest if you like :)

Answer:

Hello,

Boat speed=7 miles/h

Current speed = 1 mile/h

Step-by-step explanation:

I am going to try to explain.

Let say V the speed of the boot (V like vitesse in french)

Let say v the speed of the current.

distance=24 miles

[tex]\left\{\begin{array}{ccc}V-v&=&\dfrac{24}{4} \\V+v&=&\dfrac{24}{3} \\\end{array}\right.\\\\\left\{\begin{array}{ccc}V-v&=&6 \\V+v&=&8 \\\end{array}\right.\\\\Adding\ the\ 2\ equations\ and\ substracting\ them \\\\\\\left\{\begin{array}{ccc}2V&=&14 \\2v&=&2 \\\end{array}\right.\\\\\\\left\{\begin{array}{ccc}V&=&7 \\v&=&1 \\\end{array}\right.\\\\[/tex]

Boat speed=7 miles/h

Current speed = 1 mile/h

Answer:

MZ = 10

ZO = 10

MO = 20

XZ = 9

YZ = 7

Step-by-step explanation:

Triangles are all the same, proportionally.

X is midpoint of 14, so 7

Y for 18, so 9

Triangle with 10 is 7, 9, 10

Full triangle is double at 14, 18, MO

Since angle N is same angle, MO is double 10, so 20

Z is midpoint, so both halves are 10

Because of midpoints, XZ and YZ with 10 form same triangle as half triangle at 9, 7, and 10 respectively.

Answer:

B

Step-by-step explanation:

area=1/2×32×6.1=16×6.1=97.6 yd²

Answer:

Choice B. 97.6 yd^2

Step-by-step explanation:

B×W×.5= A

Answer:

This is what you asked me just now.

Step-by-step explanation:

Answer:

y+1/2-2y-1/2=4​

y-2y=4

-y=4

y=-4

Let  me know if this helps!

Answer:

I am so lost but if it's how many honk out of how many you saw I would assume 7/7

Answer: it wll be thursday at 7:30PM

Answer:

see image

Step-by-step explanation:

put a point on .5 on the x axis and a point on -3 on the y axis draw a line through them and shade the space under the line

Answer:

4,000mm

Step-by-step explanation:

I tryed my best

Answer:

mate...

cm to mm is by multiplying 10

400 * 10 = 4000mm

brainliest l m a o

Answer:

Step-by-step explanation:

The cross-section is an 8”×13” rectangle.

Area = 104 square inches

Answer: (b)

Step-by-step explanation:

Given

There are five consecutive integers and the least minus twice the greatest equals to -3

Suppose [tex]x,x+1,x+2,x+3,x+4[/tex] are the five consecutive integers

According to the question

[tex]\Rightarrow x-2(x+4)=-3\\\Rightarrow x-2x-8=-3\\\Rightarrow -x=8-3\\\Rightarrow x=-5[/tex]

option (b) is correct.

Answer: [tex]10, 31\ \text{years}[/tex]

Step-by-step explanation:

Given

The present age of Madison's Mother is three time that of Madison

Suppose the Present age of Madison is [tex]x[/tex], so age of her mother is [tex]3x[/tex]

After [tex]6\dfrac{1}{4}\ \text{years}[/tex], the sum of their age will be [tex]53\dfrac{3}{4}\ \text{years}[/tex]

[tex]\therefore (x+6\dfrac{1}{4})+(3x+6\dfrac{1}{4})=53\dfrac{3}{4}\\\\\Rightarrow 4x+2\times \dfrac{25}{4}=\dfrac{53\times 4+3}{4}\\\\\Rightarrow 4x+\dfrac{50}{4}=\dfrac{215}{4}\\\\\Rightarrow 4x=\dfrac{215-50}{4}\\\\\Rightarrow x=\dfrac{165}{16}\\\\\Rightarrow x= 10.31\approx 10[/tex]

Madison mother's age [tex]3x=30.93\approx 31\ \text{years}[/tex]

Answer:

Front = 30

Back = 30

Right = 30

Left = 30

Bottom = 25

Top = 16

Total = 161

Let me know if this helps!

Answer:

D. 13

Step-by-step explanation:

You just have to plug in numbers then solve.

(1,9) and (1,-4). Every coordinate is placed as (x,y)

(1,9) is labeled as (x1, y1)

(1,-4) is labeled as (x2,y2)

Now plug in the numbers.

d= Square root of (1-1)^2 + (-4-9)^2

d= Square root of 1^2 +-13^2

d= Square root of 1+169

d= Square root of 170

d= 13.04

Rounded to a whole number, the answer is 13

Answer:

D

Step-by-step explanation:

you have to substitute the values in the distance formula,in this case x2 is 1,x1 is 1,y2 is -4 and y1 is 9

d=√(x2-x1)²+(y2-y1)²

=√(1-1)²+(-4-9)²

=√(0)²+(-13)²

=√169

=13

I hope this helps

Answer:

3 11/15 miles

Step-by-step explanation:

4 1/3 - 3/5

4 5/15 - 9/15

3 20/15 - 9/15

3 11/15 miles

Answer:

sinF = [tex]\frac{11}{61}[/tex]

Step-by-step explanation:

sinF = [tex]\frac{opposite}{hypotenuse}[/tex] = [tex]\frac{EG}{FE}[/tex] = [tex]\frac{11}{61}[/tex]

The ratio which represents the sine of ∠F is [tex]\frac{11}{61}[/tex].

In a right angled triangle, the sine of an angle is the length of the side opposite the angle divided by the length of the hypotenuse.

sin θ = opposite side w.r.t θ / hypotenuse

According to the given question

We have

A right angle triangle EFG, in which

∠G = 90 degree

EG = 11

FE = 61

and,  GF = 60

Now, the opposite side with respect to ∠F is GE

and the hypotenuse is EF

Therefore, sine of ∠F = side which is opposite w.r.t ∠F/ hypotenuse

⇒ [tex]sinF=\frac{GE}{EF}[/tex]

⇒ [tex]SinF=\frac{11}{61}[/tex]

Hence, the ratio which represents the sine of ∠F is [tex]\frac{11}{61}[/tex].

Learn more about sine of an angle here:

https://brainly.com/question/13656175

#SPJ2

Answer:

correct me if I'm but i think the net cash flow is 3,790 because 2,040 a month income and 1,750 a month for other stuff. 2,040+1,750=3,790

Step-by-step explanation:

Answer:

what graph

Step-by-step explanation:

Answer:

Hshushahhahaa

Hdhddjkddjdkjd

Answer:

Area of a complete circle = PI * r^2

The shaded area is 1/3 of the circle so

Area = (PI * 9^2) / 3

Area = (254.4690049408) / 3

Area = 84.8230016469

Area = 84.82 square feet (rounded)

Step-by-step explanation: