First, write an equation system for the problem
For example, x represents the first angle and y represents the second angle
An equation for "t<span>he measure of an angle is seventeen times the measure of a complementary angle" is
</span>∴ <span>x = 17y
The sum of complementary angle is 90</span>°. It can be written as<span>
</span>∴ x + y = 90°
<span>
Second, use subtitution method to find the value of x and y
Subtitute x with 17y
x + y = 90</span>°
17y + y = 90°
18y = 90°
y = 90°/18
y = 5°
Subtitute y with 5°
x = 17y
x = 17(5)
x = 85°
The measure of each angle is 5° and 85°
Answer: a) Required minimum sample size= 219
b) Required minimum sample size= 271
Step-by-step explanation:
As per given , we have
Margin of error : E= 5% =0.05
Critical z-value for 90% confidence interval : 
a) Prior estimate of true proportion: p=28%=0.28
Formula to find the sample size :-

Required minimum sample size= 219
b) If no estimate of true proportion is given , then we assume p= 0.5
Formula to find the sample size :-

Required minimum sample size= 271
Answer:
the probability is 2/9
Step-by-step explanation:
Assuming the coins are randomly selected, the probability of pulling a dime first is the number of dimes (4) divided by the total number of coins (10).
p(dime first) = 4/10 = 2/5
Then, having drawn a dime, there are 9 coins left, of which 5 are nickels. The probability of randomly choosing a nickel is 5/9.
The joint probability of these two events occurring sequentially is the product of their probabilities:
p(dime then nickel) = (2/5)×(5/9) = 2/9
_____
<em>Alternate solution</em>
You can go at this another way. You can list all the pairs of coins that can be drawn. There are 90 of them: 10 first coins and, for each of those, 9 coins that can be chosen second. Of these 90 possibilities, there are 4 dimes that can be chosen first, and 5 nickels that can be chosen second, for a total of 20 possible dime-nickel choices out of the 90 total possible outcomes.
p(dime/nickel) = 20/90 = 2/9
The answer would be 15 but i am not sure what the problem says her answer is. if it is not 15 then her answer is wrong
The value of the angles should be. (x-40°). , (x-20°), (½x-10°) , not (x-40°) + (x-20°)+(½x-10°)
Sum of all the interior angles of a triangle is 180°.
So a equation can be made by the given data,
(x-40°) + (x-20°) + (½ x-10°) = 180°
x-40°+x-20°+½x-10° = 180°
2x+½x -60°-10° = 180°
5/2 x - 70° = 180°
5/2 x = 180° + 70°
5/2 x = 250°
x = 250° × 2/5
x = 50° × 2
x = 100°
So the angles are
x-40° = 100°-40° = 60°
x-20° = 100°–20° = 80°
½x-10° = ½(100)° - 10° = 50° -10° = 40°
The answer can be checked by putting the values of the angle we got in the second statement i.e. Sum of all the interior angles of a triangle is 180°.
60° + 80° + 40° = 100° + 80° = 180°