Answer:
75, 77
Step-by-step explanation:
Let the first odd number = 2x -1
Let the second odd number = 2x + 1
2x - 1 + 2x + 1 + 18 = 170 Combine like terms on the left.
4x + 18 = 170 Subtract 18 from both sides.
4x = 170 - 18 Combine like terms on the right
4x = 152 Divide by 4
4x/4 = 152/4
x = 38
2 * 38 - 1 = 75
2 * 38 + 1 = 77
Answer:
756 hellos
Step-by-step explanation:
Each 28 persons say hello once to every 27 persons
So, 28 × 27= 756
Answer:

Step-by-step explanation:
We can use the following trigonometrical identity:
(1)
Where
,
are angles, measured in sexagesimal degrees.
If we know that
and
, then the value of the given function is:







Answer:
d. 1/4
Step-by-step explanation:
The common ratio will be the ratio of any two adjacent terms:
(3/12)/(3/3) = (1/4)/1 = 1/4
Answer:
n=97
Step-by-step explanation:
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
Assuming the X follows a normal distribution

We know that the margin of error for a confidence interval is given by:
(1)
The next step would be find the value of
,
and 
Using the normal standard table, excel or a calculator we see that:

If we solve for n from formula (1) we got:


And we have everything to replace into the formula:

And if we round up the answer we see that the value of n to ensure the margin of error required
is n=97.