25. yes it's direct variation
26. yes
Answer:
y = -2/3x - 3
Step-by-step explanation:
First, write the equation using the slope. It should look like this: y = -2/3x + b. Next, find the y intercept by plugging in the point. This is what it looks like: -1 = -2/3(-3) + b. Multiply -2/3 by -3 to get 2. This is what it should look like now: -1 = 2 + b. Subtract 3 from both sides to get -3 = b. Go back to your original equation and plug in -3 for b. This is your final equation:
y = -2/3x - 3
Hope this helped! :)
Answer:
Step-by-step explanation:
Given that:
Population Mean = 7.1
sample size = 24
Sample mean = 7.3
Standard deviation = 1.0
Level of significance = 0.025
The null hypothesis:

The alternative hypothesis:

This test is right-tailed.

Rejection region: at ∝ = 0.025 and df of 23, the critical value of the right-tailed test 
The test statistics can be computed as:



t = 0.980
Decision rule:
Since the calculated value of t is lesser than, i.e t = 0.980 <
, then we do not reject the null hypothesis.
Conclusion:
We conclude that there is insufficient evidence to claim that the population mean is greater than 7.1 at 0.025 level of significance.
Answer:
d = 25
Step-by-step explanation:
Perhaps you want to solve for d:
(0.3d -1.5)/(3 1/3) = 0.84/(7/15)
Change the division by a fraction to multiplication by its inverse.
(0.3d -1.5)·(3/10) = (0.84)·(15/7)
0.09d -0.45 = 1.8 . . . . . . . . . . . . simplify
d - 5 = 20 . . . . . . . . . . . . . . . . . . divide by 0.09
d = 25 . . . . . . . . . . . . . . . . . . . . . add 5
_____
Grouping symbols help show what is being divided by what. Especially where mixed numbers are involved, parentheses help show that the number 3 1/3 is not supposed to be interpreted as the product of 3 and 1/3.