Answer:
225
Step-by-step explanation:
15x15=225
There is a cool trick you can do. Lets take 28 and square it.
First you round the number up. 28 rounded is 30. You rounded up by 2 (30-28=2) so you minus 2 from 28.
You are left with these two numbers, 26 and 30. Add a zero to the 26.
You now have 260 and 3 (you remove 0 on the 30 since you added it to the 26)
Then you multiply by 3.
260x3=780
Then you add the square of the number you rounded up too, which is 2.
You are left with this equation.
(2^2)+780= 784
28x28=784.
This works for numbers below 100 and integers
Students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Their replies are summarized below.
Degree of Certainty
credits earned very uncertain Somewhat Certain very certain Row tot
under 10 24 16 6 46
10 through 59 16 8 20 44
60 or more 2 14 22 38
col total 42 38 48 128
Under the assumption of independence, the expected frequency in the upper left cell is:__________.
A. 2.47
B. 14.56
C. 2.00
D. 11.09
This question is incomplete, the complete question is;
Students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Their replies are summarized below.
credits earned very deg.of certainty very Row Total
uncertain somewhat certain certain
under10 24 16 6 46
10 through 59 16 8 20 44
60 or more 2 14 22 38
col total 42 38 48 128
Under the assumption of independence, the expected frequency in the upper left cell is:__________.
A. 12.47
B. 14.56
C. 2.00
D. 11.09
Answer:
Under the assumption of independence, the expected frequency in the upper left cell is 12.47
Option A) 12.47 is the correct Option
Step-by-step explanation:
Given the data in table in the question;
the expected frequency in the upper left cell will be;
Eij = (Ti × Tj) / N
Row total Ti = 38
Column total Tj = 42
Total frequency N = 128
so we substitute
Eij = (38 × 42) / 128
= 1596 / 128
= 12.468 ≈ 12.47
Therefore Under the assumption of independence, the expected frequency in the upper left cell is 12.47
Option A) 12.47 is the correct Option
Line B crosses through the points (3,1) and (-3,-1). Using those two points, find the slope of line B.
1 1/2 x 4 1/4 = ?
PLZ ANSWER QUICKLY
Find the value of 7C7
Step-by-step explanation:
If there were 7 items, the number of ways to choose 7 out of the 7 items is only 1 way, which is to get all of them.
=> 7C7 = 1.
Evaluate the following expression.
(-5+7 x 1)-9x5
Answer:
Step-by-step explanation:
43
Identify the graph that displays the depth of water in a swimming pool after the drain is opened.
Answer:
option b is the answer because if we open drain then depth of water will decrease continuously with time and in option b graph it is clearly visible that depth and time are inversely proportional to each other so if time increases then depth of water decrease.
Answer:
b
Step-by-step explanation:
Evaluate the expression if y=6 : 30 - 24 ÷ y
Answer:
The answer is 1
Step-by-step explanation:
30 minus 24 is 6 and 6 divided by 6 is 1
14. The area of a rectangle is 375 square inches and it’s perimeter is 80 inches. Find both the length and width.
Answer:
Length [tex]=25[/tex] inches
Width [tex]= 15[/tex] inches
Step-by-step explanation:
Let [tex]l[/tex] = length of rectangle, [tex]w[/tex] = width of rectangle
Given the area and the perimeter of the rectangle, we can write:
[tex]lw = 375[/tex]
[tex]2l+2w=80[/tex]
So:
[tex]l+w = 80\div2[/tex]
[tex]=40[/tex]
[tex]l=40-w[/tex]
Now, we can use substitution to find the value of [tex]w[/tex]:
[tex]lw = 375[/tex]
[tex](40-w)w = 375[/tex]
[tex]40w-w^2 = 375[/tex]
[tex]375+w^2-40w = 0[/tex] (Quadratic equation)
[tex](w-15)(w-25) = 0[/tex]
∴ [tex]w = 15, 25[/tex]
We can use substitution again to find the value of [tex]l[/tex]
[tex]lw = 375[/tex]
[tex]l=375\div w[/tex]
[tex]=25,15[/tex]
∵ Length usually refers to the longer side of a rectangle, ∴ length [tex]=25[/tex] inches and width [tex]=15[/tex] inches.
Hope this helps :)
For the right triangle shown, which of these equations is correct?
1. all answers are correct
2. cos(53) = x/16
3. cos(53) = sin(37)
4. sin(37) = 16/x
Answer:
3
Step-by-step explanation:
3 because 37° and 53° these sum is 90°.
Answer:
3. cos(53)=sin(37)
Step-by-step explanation:
let y be the third side
cos(53)= adj/hyp
=y/16
sin(37)=opp/hyp
=y/16
therefore, sin(37)=cos(53)=y/16
Find the zero of the function.
f(x)= 4x^2– 12x+9
Answer:
The zero is x = 3/2 = 1.5
Step-by-step explanation:
We recognize that the trinomial 4 x^2 - 12 x + 9 is a perfect square trinomial, which comes from the following squared binomial:
(2 x - 3)^2
Therefore, the zeros are the x-values that verify the following:
(2 x - 3)^2= 0
that is (2 x - 3) = 0 and solving for "x":
2 x = 3
x = 3 / 2
x = 1.5
I need to Determine which two whole numbers each problem lies between. The number is 10/3
Answer:
I am not sure.
Step-by-step explanation:
-2 + 0.4x = -0.2(4x+22)
solve
Evaluate 32 divided by 1.6
show work long division
Answer:
[tex]20[/tex]
Step-by-step explanation:
[tex]-----------------------------------[/tex]
[tex]\frac{32}{1.6}[/tex] = [tex]\frac{16}{0.8}[/tex] = [tex]\frac{8}{0.4}[/tex] = [tex]\frac{4}{0.2}[/tex] = [tex]\frac{2}{0.1}[/tex]
[tex]-----------------------------------[/tex]
[tex]Since[/tex] [tex]you[/tex] [tex]could[/tex] [tex]divide[/tex] [tex]it[/tex] [tex]to[/tex] [tex]0.1[/tex], [tex]just[/tex] [tex]switch[/tex] [tex]the[/tex] [tex]decimal[/tex] [tex]with[/tex] [tex]the[/tex] [tex]0[/tex] [tex]and[/tex] [tex]take[/tex] [tex]away[/tex] [tex]the[/tex] [tex]decimal[/tex] [tex]point.[/tex] [tex]You[/tex] [tex]will[/tex] [tex]get[/tex] [tex]10[/tex]. [tex]Lastly[/tex], [tex]change[/tex] [tex]the[/tex] [tex]division[/tex] [tex]to[/tex] [tex]multiplication.[/tex]
( Remember that this does not apply to all equations. )
[tex]-----------------------------------[/tex]
[tex]When[/tex] [tex]you[/tex] [tex]multiply[/tex] [tex]10\cdot2[/tex], [tex]you[/tex] [tex]get[/tex] [tex]20.[/tex] [tex]Which[/tex] [tex]is[/tex] [tex]the[/tex] [tex]answer.[/tex]
[tex]-----------------------------------[/tex]
Hope this helps! <3
[tex]-----------------------------------[/tex]
plz help!! will give brainliest!!
Type the expression that results from the following series of steps:
Start with n and divide by 2.
help again again again
Answer:
it's the last choice, by process of elimination that's the only one that includes the 4. and of course the math adds up
Simplify (X^5/8)^2/3
Answer: Its x5/12
Step-by-step explanation: Hope this helps!!1 <3
Triviaaaa for you smart people, is Sixteen times some number equals 60, an equation or expression?
Answer:
an equation
Step-by-step explanation:
this is because there is an unknown value (some number)
If 3 times the difference of x and y is -30, and 2/3 of x plus 1/2 of y is 19, what are x and y
Answer:
x = 12 and y = 22
Step-by-step explanation:
It is given that,
3 times the difference of x and y is -30
3(x-y) = -30
3x-3y = -30 ....(1)
2/3 of x plus 1/2 of y is 19.
[tex]\dfrac{2x}{3}+\dfrac{y}{2}=19\\\\\dfrac{4x+3y}{6}=19\\\\4x+3y=114\ ...(2)[/tex]
Add equation (1) and (2).
3x-3y + 4x+3y = -30 +114
7x = 84
x = 12
Put the value of x in equation (1)
3x-3y = -30
3(12)-3y = -30
36+30 = 3y
3y = 66
y = 22
Hence, the value of x and y are 12 and 22.
A dozen is how much in maths?
Answer:
well for me it's
Step-by-step explanation:
12
But a german dozen is 13
please give me brainlest
[tex]\frac{d}{dx} \int t^2+1 \ dt[/tex]
There is a 2x on the bottom and x^2 on top of the integral symbol
Please help me my teacher did not teach us this:(
Answer:
[tex]\displaystyle{\frac{d}{dx} \int \limits_{2x}^{x^2} t^2+1 \ \text{dt} \ = \ 2x^5-8x^2+2x-2[/tex]
Step-by-step explanation:
[tex]\displaystyle{\frac{d}{dx} \int \limits_{2x}^{x^2} t^2+1 \ \text{dt} = \ ?[/tex]
We can use Part I of the Fundamental Theorem of Calculus:
[tex]\displaystyle\frac{d}{dx} \int\limits^x_a \text{f(t) dt = f(x)}[/tex]Since we have two functions as the limits of integration, we can use one of the properties of integrals; the additivity rule.
The Additivity Rule for Integrals states that:
[tex]\displaystyle\int\limits^b_a \text{f(t) dt} + \int\limits^c_b \text{f(t) dt} = \int\limits^c_a \text{f(t) dt}[/tex]We can use this backward and break the integral into two parts. We can use any number for "b", but I will use 0 since it tends to make calculations simpler.
[tex]\displaystyle \frac{d}{dx} \int\limits^0_{2x} t^2+1 \text{ dt} \ + \ \frac{d}{dx} \int\limits^{x^2}_0 t^2+1 \text{ dt}[/tex]We want the variable to be the top limit of integration, so we can use the Order of Integration Rule to rewrite this.
The Order of Integration Rule states that:
[tex]\displaystyle\int\limits^b_a \text{f(t) dt}\ = -\int\limits^a_b \text{f(t) dt}[/tex]We can use this rule to our advantage by flipping the limits of integration on the first integral and adding a negative sign.
[tex]\displaystyle \frac{d}{dx} -\int\limits^{2x}_{0} t^2+1 \text{ dt} \ + \ \frac{d}{dx} \int\limits^{x^2}_0 t^2+1 \text{ dt}[/tex]Now we can take the derivative of the integrals by using the Fundamental Theorem of Calculus.
When taking the derivative of an integral, we can follow this notation:
[tex]\displaystyle \frac{d}{dx} \int\limits^u_a \text{f(t) dt} = \text{f(u)} \cdot \frac{d}{dx} [u][/tex]where u represents any function other than a variableFor the first term, replace [tex]\text{t}[/tex] with [tex]2x[/tex], and apply the chain rule to the function. Do the same for the second term; replace
[tex]\displaystyle-[(2x)^2+1] \cdot (2) \ + \ [(x^2)^2 + 1] \cdot (2x)[/tex]Simplify the expression by distributing [tex]2[/tex] and [tex]2x[/tex] inside their respective parentheses.
[tex][-(8x^2 +2)] + (2x^5 + 2x)[/tex] [tex]-8x^2 -2 + 2x^5 + 2x[/tex]Rearrange the terms to be in order from the highest degree to the lowest degree.
[tex]\displaystyle2x^5-8x^2+2x-2[/tex]This is the derivative of the given integral, and thus the solution to the problem.
Can someone please help me :(
Answer:
1
Step-by-step explanation:
2x + 1 = -3x + 6
add 3x
5x + 1 = 6
subtract 1
5x=5
Divide by 5
x=1
If this is correct, please mark brainliest!
Answer:
x=7
Step-by-step explanation:
2x + 1 = 15
-3x+6 = - 15
Since they are equal the equation is true
What equation represents the proportional relationship displayed in the table ?
Answer:
y=5x
Step-by-step explanation:
Answer:
5
Step-by-step explanation:
When you divide each y-value by its corresponding x-value, you get 5.
For example, 10/2 = 5; 20/4 = 5
y is always 5 times x.
y = 5x
Answer: 5
Find sin θ. Right Triangle Trigonometry.
Answer:
A. 16/20
General Formulas and Concepts:
Trigonometry
[Right Triangles Only] SOHCAHTOA[Right Triangles Only] sin∅ = opposite over hypotenuseStep-by-step explanation:
Step 1: Identify
Angle θ
Opposite Leg = 16
Hypotenuse = 20
Step 2: Find Ratio
Substitute [Sine]: sinθ = 16/20Answer:
A. 16/20
Step-by-step explanation:
The sine ratio is the opposite leg over the hypotenuse, opp/hyp.
For angle theta, the opposite leg is 16. The hypotenuse is 20.
sin (theta) = 16/20
Answer: A. 16/20
I need this answered soon please!
Answer:
its B
Step-by-step explanation:
simplify the radical by breaking the radicand up into the product of known factors.assuming real numbers
URGENT PLEASE I NEED HELP AND KINDLY SHOW THE SOLUTION/S AS WELL :))
Answer:
1. Steve's age is 18 and Anne's age is 8.
2. Max's age is 17 and Bert's age is 11.
3. Sury's age is 19 and Billy's age is 9.
4. The man's age is 30 and his son's age is 10.
Step-by-step explanation:
1. Let us assume that:
S = Steve's age now
A = Anne's age now
Therefore, in four years, we have:
S + 4 = (A + 4)2 - 2
S + 4 = 2A + 8 - 2
S + 4 = 2A + 6 .................. (1)
Three years ago, we have:
S - 3 = (A - 3)3
S - 3 = 3A - 9 ................................ (2)
From equation (2), we have:
S = 3A - 9 + 3
S = 3A – 6 …………. (3)
Substitute S from equation (3) into equation (1) and solve for A, we have:
3A – 6 + 4 = 2A + 6
3A – 2A = 6 + 6 – 4
A = 8
Substitute A = 8 into equation (3), we have:
S = (3 * 8) – 6
S = 24 – 6
S = 18
Therefore, Steve's age is 18 while Anne's age is 8.
2. Let us assume that:
M = Max's age now
B = Bert's age now
Therefore, five years ago, we have:
M - 5 = (B - 5)2
M - 5 = 2B - 10 .......................... (4)
A year from now, we have:
(M + 1) + (B + 1) = 30
M + 1 + B + 1 = 30
M + B + 2 = 30 .......................... (5)
From equation (5), we have:
M = 30 – 2 – B
M = 28 – B …………………… (6)
Substitute M from equation (6) into equation (4) and solve for B, we have:
28 – B – 5 = 2B – 10
28 – 5 + 10 = 2B + B
33 = 3B
B = 33 / 3
B = 11
Substituting B = 11 into equation (6), we have:
M = 28 – 11
M = 17
Therefore, Max's age is 17 while Bert's age is 11.
3. Let us assume that:
S = Sury's age now
B = Billy's age now
Therefore, now, we have:
S = B + 10 ................................ (7)
Next year, we have:
S + 1 = (B + 1)2
S + 1 = 2B + 2 .......................... (8)
Substituting S from equation (7) into equation (8) and solve for B, we have:
B + 10 + 1 = 2B + 2
10 + 1 – 2 = 2B – B
B = 9
Substituting B = 9 into equation (7), we have:
S = 9 + 10
S = 19
Therefore, Sury's age is 19 while Billy's age is 9.
4. Let us assume that:
M = The man's age now
S = His son's age now
Therefore, now, we have:
M = 3S ................................... (9)
Five years ago, we have:
M - 5 = (S - 5)5
M - 5 = 5S - 25 ................ (10)
Substituting M from equation (9) into equation (10) and solve for S, we have:
3S - 5 = 5S – 25
3S – 5S = - 25 + 5
-2S = - 20
S = -20 / -2
S = 10
Substituting S = 10 into equation (9), we have:
M = 3 * 10
M = 30
Therefore, the man's age is 30 and his son's age is 10.
CAN SOMEONE HELP ME WITH THIS??? I WILL MARK BRAINLIEST!!!
Answer:
no
Step-by-step explanation:
it has no number behind it so it is just 12 which is a integer
Answer:
Amelia is correct.
According to Google, an integer is a whole number, not a fraction. Therefore, she is correct.
a grandfather is nine times older than his granddaughter. in 8 years the grandfather will be five times older than his granddaughter how old is each of them now?
Answer:
Grandfather is 72 and granddaughter is 8
Step-by-step explanation:
f is grandfather and d is granddaughter.
f = 9d
f+8 = 5(d+8)
9d+8=5d+40
4d=32
d=8
f=9*8=72
Answer:
the grandpa is 72 the little girl is 8
Step-by-step explanation:
The temperature in a chemical reactor was measured every half hour under the same conditions. The results were 78.1°C, 79.2°C, 78,9°C, 80.2°C, 78.3°C, 78.8°C. 79.4°C.
the mean ?
Answer:
72.2
Step-by-step explanation:
The mean of the data is 78.98.
What is Mean?The sum of all values divided by the total number of values determines the mean (also known as the arithmetic mean, which differs from the geometric mean) of a dataset. The term "average" is frequently used to describe this measure of central tendency.
For example,
To calculate the mean,
= (3 + 11 + 4 + 6 + 8 + 9 + 6 = 47). Then you divide the total sum by the number of scores =(47 / 7 = 6.7).
Given:
Data: 78.1°C, 79.2°C, 78,9°C, 80.2°C, 78.3°C, 78.8°C. 79.4°C.
Now, the mean of the data
= Sum of data/ Total number of data
= 78.1+ 79.2+ 78.9+ 80.2+ 78.3+ 78.8+ 79.4 / 7
= 552.9/7
= 78.98
Hence, the mean of the data is 78.98.
Learn more about Mean here:
https://brainly.com/question/15323584
#SPJ2
If t=2 what is the value of 13-2t
Answer:
9
Step-by-step explanation:
plug in t=2 into equation
so
13-2(2)
=13-4
=9