Answer:
So we reject the null hypothesis and accept the alternate hypothesis that rats learn slower with sound.
Step-by-step explanation:
In this data we have
Mean= u = 18
X= 38
Standard deviation = s= 6
1) We formulate the null and alternate hypothesis as
H0: u = 18 against Ha : u > 18 One tailed test .
2) The significance level alpha = ∝= 0.05 and Z alpha has a value ± 1.645 for one tailed test.
3)The test statistics used is
Z= X- u / s
z= 38-18/6= 3.333
4) The calculated value of z = 3.33 is greater than the z∝ = 1.645
5) So we reject the null hypothesis and accept the alternate hypothesis that rats learn slower with sound.
First we set the criteria for determining the true of value of the variable. That whether the rats learn in less or more than 18 trials.
Then we find the value of z for the given significance value given and the test about to be checked.
Then the test statistic is determined and calculated.
Then both value of z and z alpha re compared. If the test statistics falls in the rejection region reject the null hypothesis and conclude alternate hypothesis is true.
The figure shows that the calulated z value lies outside the given z values
Answer:12
Step-by-step explanation:
Let the numbers be a and b
a-3b=5 ........equation (1)
There product is :
ab=68 ..........equation (2)
From equation (1)
a-3b=5
Make a the subject of the formula
a=5+3b. ........equation (3)
Substitute equation (3) into equation (2)
(5+3b)b=68
3(b^2)+3b-68=0
The product is -204b^2(17 and -12)
(b+17)(b-12)=0
b=-17 or b=12
So the number is 12
Answer:
Hope this helps. Mark as brainliest please!
Step-by-step explanation:
10-3^3/9
10-27/9
10-3
7
Answer: -4
Work: So, to get -4, we need to simplify the equation. If you see any equation with +(- that's subtraction. So, with the rule, this equation is basically 8-12, and that's -4.
The answer is B)
x2+2x−3=0
Factor left side of equation.
(x−1)(x+3)=0
Set factors equal to 0.
x−1=0 or x+3=0
x=1
or
x=−3