The photographer got the baby to smile in 30% of the photos he took. If the baby smiled in 12 photos how many photos did the photographer take

Answer:

8 is 50% of 16

Step-by-step explanation:

since 8 is half of 16

Step-by-step explanation:

3% = 0.03

we are looking for the 3rd percentile of Z.

checking the Z-table we find as the entry closest to 0.03 to be 0.0301 at z = -1.8 and 0.8.

so, the 3rd percentile of Z is -1.88

the cutoff number (the number of miles, where max. 3% of the tires will qualify for a refund) is

mean value + Z× standard deviation

22000 + -1.88 × 3100 = 16,172 ≈ 16,170

so, b. is correct

Answer:

?=5

Step-by-step explanation:

4/5-2/5=2/5

First we must replace ? with x for an unknown value and then solve.

Answer:

A.

Step-by-step explanation:

This equation has no solution.

Answer:

a+(n-1)14

Step-by-step explanation:

ok so

a=the first number which is 16.50

n=the term.eg since 30.50 is the second number it's the second term

14 is the common difference d

I found 14 like this

30.50=16.50+(2-1)d

Therefore d=14

hence the formula is a+(n-1)14

Answer:

i am not really sure but

Step-by-step explanation:

The way the angles are labeled tell you that they are all congruent. The two triangles you see here also share the side that joins them. Then by the angle-side-angle postulate, the two triangles are congruent, so x + 23 = 13, or x = -10.

Answer:

The sum is 12276 . 

Step-by-step explanation:

This expression can be written as:Σ10i=1(6×2n)=6×Σ10i=12n

The last expression is a sum of a finite geometrical sequence for which: a1=2,q=2,n=10. This sum can be calculated as:S10=2×1−2101−2=2×210−12−1=2×(210−1)==2×1023=2046So the value of the first expression is: 6×2046=12276

Mark me brainliest!!

the answer is : 9.72×10^4 or 972×10^2

Step-by-step explanation:

l didn't agree with the answer because

(1.72×10^4 + 8×10^4)

form above take common i.e., 10^4 so we get,

10^4 (1.72+8.00)

10^4(9.72)

so we get the answer is : 9.72×10^4 or

(972÷100)10^4

972 × 10^-2 ×10^4

972× 10^(-2+4)

972× 10^2

Answer: C

Step-by-step explanation:

The equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k) are the coordinates of the vertex and a is a multiplier

Here (h, k) = (3, - 0.5), thus

y = a(x - 3)² - 0.5

To find a substitute either of the x- intercepts into the equation.

Using (4, 0), then

0 = a(4 - 3)² - 0.5 = a - 0.5 ( add 0.5 to both sides )

a = 0.5

y = 0.5(x - 3)² - 0.5 ← equation of quadratic function

Hey there!

8^2 ÷  4^2 - 36 ÷  9

= 8 × 8 ÷ 4 × 4 - 36 ÷ 9

= 64 ÷ 16 - 36 ÷ 9

= 4 - 36 ÷ 9

= 4 - 4

= 0

Therefore, your answer is: 0

Good luck on your assignment & enjoy your day!

~Amphitrite1040:)

Answer:

x = 3 inches

Step-by-step explanation:

Let x = the side of the original square, so the area is x²

After increasing, the side becomes x + 6. so the area becomes (x + 6)²

The area is multiplied by 9 means

(x + 6)² = 9 * x²

Take a square root, get

x + 6 = 3 * x

2x = 6

x = 3 inches

Let L represent the side length of the original square.

Note that:

1. Square root both sides:

2. Simplify the RHS:

3. Subtract L from each side.

4. Divide 2 both sides.

=> 81 ÷ 9 = 9 (True)

This shows that the area of the original square is 9 times smaller than the increased square.

Answer:

7

Step-by-step explanation:

The letter for sausage or red sauce is S at the end and R in the middle.

Counting, there is 7 outcomes that have either S at the end or R in the middle.

Step-by-step explanation:

interest =

[tex] \frac{3}{100} \times 1810[/tex]

therefore

interest = $54.3 after a year

pls give brainliest

Answer:

54.3

Step-by-step explanation:

Interest earned = Prt

where P is the initial investment and r is the interest rate and t is time

Interest earned = 1810*0.03*1=54.3

Answer:

D

Step-by-step explanation:

The shaded area is the intersection of the two inner areas of the two circles.

Because the area is inside both circles, the two inequalities must be less than or equal to the equation of the circles.

(If the inequalities are greater than or equal to the equation of the circles, the shaded areas will lie outside the circle.)

Hence, choice D is the correct choice.

It may assist to rewrite the inequalities such that it becomes apparent the equations are indeed less than or equal to the constant:

[tex]\displaystyle x^2 + (y+6)^2 \leq 21 \text{ and } (x+8)^2 + y^2 \leq 84[/tex]

Answer:

D

Step-by-step explanation:

Answer:

Slope: 20/7

Y-intercept: 0

Step-by-step explanation:

Hello!

This is a regular graph, and we can find out several things from it, including slope and y-intercept.

The slope is basically how steep or flat the line is. The more flat it is, the bigger the slope. The more steep it is, the more smaller the slope. We can find the slope by using rise over run, seeing how many values it rises over how many values it runs over the x-axis.

The y-intercept is basically where the line starts from in the y-axis. The y-axis is a vertical line usually at the left most area.

To find out the slope, we can see the best fit blue line, and we have to find the most accurate slope. In this problem, the line doesn't go through perfectly with the grid at until around (14, 40). Don't get mistaken for (2,5)! It's not an accurate slope. Since it goes UP and rises 40 and 'runs' 14 units, the slope is that but simplified.

\frac{40}{14} =\frac{20}{7}

The y-intercept is where the line starts from the y-axis, where it labels 'cars'. As you can see, the blue line starts at zero, so there is no y-intercept.

To take it further, the equation of the line is y=mx+b, where m is the slope and b is the y-intercept. In this problem, the equation would be

y=[tex]\frac{20}{7}[/tex]x.

Hope this helped!

Answer:

this guy is half right

Step-by-step explanation:

0 is right but not 20/7

(5,-12) is located in the fourth quadrant.

Because 5 being positive and 12 being negative it lies in the 4th quadrant.

Step-by-step explanation:

The scale factor used to represent the model from the real object size is y = (260/3)x

An equation is an expression that shows the relationship between two or more numbers and variables.

Let y represent the real object size and x represent the size of the model.

Given that:

y = (260/3)x

The scale factor used to represent the model from the real object size is y = (260/3)x

Find out more on equation at: https://brainly.com/question/2972832

Answer:

k≥12

Step-by-step explanation:

if k's smallest amount is 12, k has to be bigger (greater than) or equal to 12

therefore:

k≥12

[tex]f(x) = 4 {x}^{2} - 6x + 11[/tex]

[tex]f(10 + h) = 4 ({10 + h})^{2} - 6(10 + h) + 11 \\ [/tex]

[tex]f(10 + h) = 4(100 + 20h + {h}^{2}) - 60 - 6h + 11 \\ [/tex]

[tex]f(10 + h) = 400 + 80h + 4 {h}^{2} - 60 - 6h + 11 \\ [/tex]

[tex]f(10 + h) = 4{h}^{2} + 74h + 351[/tex]

_____________________________________________

[tex]f(10) = 4 ({10})^{2} - 6(10) + 11[/tex]

[tex]f(10) = 400 - 60 + 11[/tex]

[tex]f(10) = 351[/tex]

_____________________________________________

[tex] \frac{f(10 + h) - f(10)}{h} = \\ [/tex]

[tex] \frac{4 {h}^{2} + 74h + 351 - (351)}{h} = \\ [/tex]

[tex] \frac{4 {h}^{2} + 74h }{h} = \\ [/tex]

[tex] \frac{4 {h}^{2} }{h} + \frac{74h}{h} = \\ [/tex]

[tex]4h + 74[/tex]

_____________________________________________

[tex]ah + b[/tex]

[tex]4h + 74[/tex]

So :

[tex]a = 4[/tex]

[tex]b = 74[/tex]

I think your question seems like :-

Find the maximum and minimum values of f(x,y) = 2+2x+4y-x²-y² on the triangular region in the first quadrant bounded by the lines x = 0, y = 0, y = 9-x. The reason is below :

If you see carefully, the given lines were x = 0, y = 0, y = 9x , also these lines forms a Triangle in first quadrant (Given) , but these all lines doesn't form a triangle in 1st quadrant , we can't change the other two lines (As those two lines will work as permanent sides and support for the triangle) but third one can be , also neither 9 + x nor (9/x) can't form triangle in 1st quadrant with the given other two lines .Only with y = 9 - x the given situation can be achieved

But before starting the question let's recall some of the concepts :-

For a given function let it be f(x,y) ,

Where ,

Now , consider the function ;

[tex]{:\implies \quad \sf f(x,y)=2+2x+4y-x^{2}-y^{2}}[/tex]

Partial Differentiating both sides w.r.t.x

[tex]{:\implies \quad \sf \dfrac{\partial f}{\partial x}=2-2x}[/tex]

Now , partial differentiating both sides w.r.t.y

[tex]{:\implies \quad \sf \dfrac{\partial^{2}f}{\partial x\partial y}=0}[/tex]

Now , consider ;

[tex]{:\implies \quad \sf \dfrac{\partial f}{\partial x}=2-2x}[/tex]

Partial differentiating both sides w.r.t.x

[tex]{:\implies \quad \sf \dfrac{\partial^{2}f}{\partial x^{2}}=-2}[/tex]

Now , consider ;

[tex]{:\implies \quad \sf f(x,y)=2+2x+4y-x^{2}-y^{2}}[/tex]

Partial differentiating both sides w.r.t.y

[tex]{:\implies \quad \sf \dfrac{\partial f}{\partial y}=4-2y}[/tex]

Now , partial differentiating both sides w.r.t.y

[tex]{:\implies \quad \sf \dfrac{\partial^{2}f}{\partial y^{2}}=-2}[/tex]

Now to find the critical points , first order partial derivative of f(x,y) both w.r.t.x and w.r.t.y must be 0. So , if you equate them to 0 , you will get x = 1 and y = 2. So critical point is only one i.e (1,2)

Now , from the above conditions , let calculate AC - B² first , from which we will get maxima or minima

[tex]{:\implies \quad \sf (-2)(-2)-(0)^{2}}[/tex]

[tex]{:\implies \quad \sf 4\> 0}[/tex]

So , AC - B² > 0 and also A < 0 , so maxima at (1,2) , to find maxima we need to put x = 1 , y = 2 in f(x,y) i.e f(1,2) = 2 + 2(1) + 4(2) - 1² - 2² = 7 . Now , for minima , draw the triangle see attachment 1 . Now , in the attachment critical points are (0,9) , (0,0) and (9,0) . Now , we need to find f(x,y) at these all points too . If you calculate then you will get f(0,9) = -43 , f(0,0) = 2 and f(9,0) = -61 , out of which -61 is minimum

So , the required maxima and minima are 7 and -61

Note :- Also , refer to the attachments no. 2,3,4 as well for why I choosed the third line to be 9 - x rather than others.

Answer:

19

Step-by-step explanation:

because you inverse the operation

5 ×3 = 15

15 + 4 = 19

Answer:

q = 6

Step-by-step explanation:

30/5 = 6

5(6)/5

30/5

6

Have an amazing day!!

PLEASE RATE AND MARK BRAINLIEST!!!

Answer:

4.5km/h

Step-by-step explanation:

Here we know that she does 9 km per 2 hours. If we know how much she can travel in 2 hours it's very easy to find out how much she travels in 1. Because half of 2 hours is one hour. So we can simply half 9 km to find how much she travels in 1 hour:

9/2 = 4.5

4.5km/h

I hope this makes sense :)

Answer:

4.5 km per hour

.........

.....

Answer:

Of course yes

Step-by-step explanation:

We first look at the ones place. So is 3>2? Yes, so the answer is yes.

2.5d ≤ 80

d ≤ 160 / 5

d ≤ 32

card will last 32 days

Answer:

Step-by-step explanation:

No solutions, the two lines are parallel.

An easy way to spot it is to put the second in slope-intercept form ([tex]y=5x+40[/tex]) and notice they have the same slope