Answer:
The first piece is 5 inches long, while the second is 15 inches and the third one is 20 inches.
Step-by-step explanation:
To determine the length of the 3 pieces, knowing that the total of the board is 40 inches, and that the second measures 3 times more than the first and the third measures 4 times more than the first, the following equation must be performed:
X + 3X + 4X = 40
8X = 40
X = 40/8
X = 5
Therefore, the first piece is 5 inches long, while the second is 15 inches and the third 20 inches.
Answer: A
Step-by-step explanation:
To find the inner product of two vectors (a,b) and (c,d) you would use the equation (a * c) + (b * d)
So for (7,2) and (0,-2) the inner product would be
(7 * 0) + (2 * -2)
= 4
The vectors are only perpendicular when the inner product is equal to 0. Since it is equal to -4 in this case, the vectors are not perpendicular.
A -4; no
Answer:
15 days
Step-by-step explanation:
Don't you mean 1/3? If so,
5 cans
-------------------- = 15 days
1/3 can/daily
Answer:
You must survey 784 air passengers.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
The margin of error is:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
Assume that nothing is known about the percentage of passengers who prefer aisle seats.
This means that 
, which is when the largest sample size will be needed.
Within 3.5 percentage points of the true population percentage.
We have to find n for which M = 0.035. So
You must survey 784 air passengers.
