Answer: INDEPENDENT SAMPLES T-TEST
Step-by-step explanation:
Given that;
sample size n₁ = 40, sample size n₂ = 40
sample mean x₁ = 32.9, sample mean x₂ = 30.6
Standard deviation S₁ = 4.4, Standard deviation S₂ = 5.1
Now
NULL hypothesis H₀ : u₁ = u₂
and Alternative hypothesis H₁ : u₁ > u₂
Therefore based on the information provided above, the type of test that should be used to determine whether the level of nicotine are now lower than what they were 10 years ago is the INDEPENDENT SAMPLES T-TEST
Step-by-step explanation:
s = side of square
l = length of rectangle = s + 3 cm
w = width of rectangle = s - 2 cm
s² + 30 = (s + 3)(s - 2) = s² + - 2s + 3s - 6 = s² + s - 6
30 = s - 6
s = 36 cm
Answer:
{x,y} = {2,-2}
Step-by-step explanation:
System of Linear Equations entered :
[1] 7x + 3y = 8
[2] 3x - 4y = 14
Graphic Representation of the Equations :
3y + 7x = 8 -4y + 3x = 14
Solve by Substitution :
// Solve equation [2] for the variable x
[2] 3x = 4y + 14
[2] x = 4y/3 + 14/3
// Plug this in for variable x in equation [1]
[1] 7•(4y/3+14/3) + 3y = 8
[1] 37y/3 = -74/3
[1] 37y = -74
// Solve equation [1] for the variable y
[1] 37y = - 74
[1] y = - 2
// By now we know this much :
x = 4y/3+14/3
y = -2
// Use the y value to solve for x
x = (4/3)(-2)+14/3 = 2
Solution :
{x,y} = {2,-2}
Answer:
<em>A: 960d = 52000 + 680d</em>
<em>B: It will take 137 days to start making a profit.</em>
Step-by-step explanation:
Part A:
She begins to make a profit when the income becomes greater than the expenses. You can write an inequality or an equation. I'll write an equation that finds when the income equals the expenses. After this point, she will begin making a profit.
income = expenses
income: the combined amount all students pay
All students pay a total of $960 per day. In d days, they pay 960d.
Total income: 960d
expenses: the original fixed amount plus the daily cost
The original fixed amount is $52,000. The daily cost is $680, so in d days, she spends 680d
Total expenses: 52000 + 680d
income = expenses
The equation is:
960d = 52000 + 680d
Part B:
Subtract 580d from both sides.
380d = 52000
Divide both sides by 380.
d = 136.84
The number of days is 136.84, or just under 137 days.
It will take 137 days to start making a profit.
Answer:
D (assuming f(x)=-3x^2+4x+6)
Step-by-step explanation:
Let's find f(2) and f(3).
I'm going to make the assumption you meant f(x)=-3x^2+4x+6 (please correct if this is not the function you had).
f(2) means replace x with 2.
f(2)=-3(2)^2+4(2)+6
Use pemdas to simplify: -3(4)+4(2)+6=-12+8+6=-4+6=2.
So f(2)=2
f(3) means replace x with 3.
f(3)=-3(3)^2+4(3)+6
Use pemdas to simplify: -3(9)+4(3)+6=-27+12+6=-15+6=-9
So f(3)=-9
-9 is smaller than 2 is the same as saying f(3) is smaller than f(2) or that f(2) is bigger than f(3).