Answer:
We accept H₀
Step-by-step explanation:
Normal Distribution
size sample n = 69
sample mean 18.94
standard deviation 8.3
Is a one tailed-test to the left we are traying of find out is we have enough evidence to say that the mean is less than 20 min.
1.-Test hypothesis H₀ ⇒ μ₀ = 20
Alternative hypothesis Hₐ ⇒ μ₀ < 20
2.- Critical value
for α = 0.1 we find from z Table
z(c) = - 1.28
3.-We compute z(s)
z(s) = [ ( μ - μ₀ ) / (σ/√n) ⇒ z(s) = [( 18.94 - 20 )*√69)/8.3]
z(s) = ( -1.06)*8.31/8.3
z(s) = - 1.061
4.- We compare
z(c) and z(s) -1.28 > -1.061
Then z(c) > z(s)
z(s) in inside acceptance region so we accept H₀
We will solve this by suing simultaneous equations,
⇒ 5s + 3j = 87
4s + 2j = 64
Multiply the first equation with 4 and the second one with 5, this is to get one of the values equal so that we can cancel them out,
⇒ (5s + 3j = 87) × 4
(4s + 2j = 64) × 5
∴ ⇒ 20s + 12j = 348
20s + 10j = 320
Subtract both the equations. This is how your result (after subtraction) should look like,
⇒ 2j = 28
∴ ⇒ j = $14
Now replace the value of 'j' in one of the original equations,
⇒ 4s + 2(14) = 64
⇒ 4s + 28 = 64
⇒ 4s = 64 - 28
⇒ 4s = 36
∴ ⇒ s = $9
Therefore, one pair of jeans cost $14 and a shirt costs $9
Hope you understood! Feel free to ask me if you didn't understand a step.
21n+14 you have to find the value of n
Substitution
-2x+8=x^2-9x+18
x^2-7x+10=0
Factoring, we get
(x-5)(x-2)=0
x=5, x=2
If x equals 5,
y=-2(5)+8=
-10+8=
-2
Therefore, we derive our first solution:
<h2><u><em>
x=5,</em></u></h2><h2><u><em>
y=-2</em></u></h2>
Now we solve for our second x
If x=2,
y=-4+8=
4
Therefore, we derive our second solution:
<h2><u><em>
x=2</em></u></h2><h2><u><em>
y=4</em></u></h2>
<u><em></em></u>
-Hunter