Important notes:
3 sides 1 angle - COSINE RULE
2 sides 2 angle - SINE RULE
since, the question wants to find the length of BC. In the end we will have 3 sides and 1 angle and use cosine rule
formula of cosine rule:
a² = b² + c² - 2bc Cos A° (to find the length)
Cos A° = b² + c² - a² / 2bc ( to find the angle, if there is given three sides and have to find the angle)
So just substitute,
a² = 13² + 15² - 2(13)(15) Cos 95°
a = 20.6 or 21
Answer:
332 ft²
Step-by-step explanation:
A rectangular garden measures 33 ft by 46 ft. Surrounding (and bordering) the garden is a path 2 ft. Find the area of this path. Be sure to include the correct unit in your answer.
Solution:
The area of the rectangular garden = length * breadth = 33 ft. * 46 ft. = 1518 ft²
Since the path surrounding the garden is 2ft, the length of the path with the garden = 46 + 2 + 2 = 50 ft
The width of the path with the garden = 33 + 2 + 2 = 37 ft.
Area of the path with the garden = length * breadth = 50 ft * 37 ft = 1850 ft².
Area of the path = 1850 ft² - 1518 ft.² = 332 ft²
We assume the lunch prices we observe are drawn from a normal distribution with true mean
and standard deviation 0.68 in dollars.
We average
samples to get
.
The standard deviation of the average (an experiment where we collect 45 samples and average them) is the square root of n times smaller than than the standard deviation of the individual samples. We'll write

Our goal is to come up with a confidence interval (a,b) that we can be 90% sure contains
.
Our interval takes the form of
as
is our best guess at the middle of the interval. We have to find the z that gives us 90% of the area of the bell in the "middle".
Since we're given the standard deviation of the true distribution we don't need a t distribution or anything like that. n=45 is big enough (more than 30 or so) that we can substitute the normal distribution for the t distribution anyway.
Usually the questioner is nice enough to ask for a 95% confidence interval, which by the 68-95-99.7 rule is plus or minus two sigma. Here it's a bit less; we have to look it up.
With the right table or computer we find z that corresponds to a probability p=.90 the integral of the unit normal from -z to z. Unfortunately these tables come in various flavors and we have to convert the probability to suit. Sometimes that's a one sided probability from zero to z. That would be an area aka probability of 0.45 from 0 to z (the "body") or a probability of 0.05 from z to infinity (the "tail"). Often the table is the integral of the bell from -infinity to positive z, so we'd have to find p=0.95 in that table. We know that the answer would be z=2 if our original p had been 95% so we expect a number a bit less than 2, a smaller number of standard deviations to include a bit less of the probability.
We find z=1.65 in the typical table has p=.95 from -infinity to z. So our 90% confidence interval is

in other words a margin of error of
dollars
That's around plus or minus 17 cents.
Answer:
27 15/28 degrees
Step-by-step explanation:
Since we are adding 21 1/4 to 6 2/7, we need to find the LCD, or, least common denominator, so that we can add 1/4 and 2/7 together.
1*4=4 1*7=7
2*4=8 2*7=14
3*4=12 3*7=21
4*4=16 <u>4*7=28</u>
5*4=20
6*4=24
<u>7*4=28</u>
Since we had to multiply 7 four times to get it equal to 28, we need to take 2/7 * 4/4. This will give you 8/28. Then, since we multiplied 4 seven times to get it equal to 28, we need to take 1/4 *7/7. This will give you 7/28. Finally, you need to add 8/28 and 7/28 since they now share the same denominator.
8/28 + 7/28=15/28
For our last step, we need to add the whole numbers together so the answer is complete.
21+6=27
27+15/28= 27 15/28 degrees
So we convert both to improper fractions.
38/7 and 1/16
Now we make them the same denominator
608/112 and 7/112
Now we divide 608 by 7
Maximum amount which can be given is 85 scholars.
Give me brainliest answer!