Answer:
22.8 and 37.5
Step-by-step explanation:
Given the
The weights (in pounds) of 18 preschool children are
32, 20, 25, 27, 31, 22, 30, 23, 44, 37, 33, 45, 41, 24, 34, 21, 39, 29
To find its 20th percentile and 75th percentile.
In ascending order we get like this
Position X (Asc. Order)
1 20
2 21
3 22
4 23
5 24
6 25
7 27
8 29
9 30
10 31
11 32
12 33
13 34
14 37
15 39
16 41
17 44
18 45
Percentile position = (no of entries +1)20/100 = 19/5 = 3.8
Since posiiton is not integer we use interpolation method.
The value of 3.8 - 3 = 0.8 corresponds to the proportion of the distance between 22 and 23 where the percentile we are looking for is located at.
Hence 20th percentile = 
So answer is 22.8
----------------------
75th percentile
Percentile posiiton = 19(75)/100 = 14.25
75th percentile= 
To convert 15 ft to centimeters you have to multiply 15 x 30.48, since 1 ft is 30.48 cms
So, if you want to calculate how many centimeters are 15 feet you can use this simple rule.
If arctan 4/3 = the tangent of that angle will be 4/3 , opposite 4 over adjacent 3
Now, you only have to take the sin of that angle it's opposite 4 over hypotenuse 5.
You will get that the answer is 4/5
hope this helps
So, in order to solve this problem, I will set up an equation. First, let's make x= the # of hours it takes Mr. Itol to complete a computer task, and since his assistant takes twice as long, lets make 2x=the # of hours it takes the assistant to complete the task. We also know that it takes the two of them 6 hours to complete the task together. We can now set up the following equation:

Now, in order to be able to solve this, we have to find the least common denominator, and then we can cancel out the denominators to solve for the top part. The LCD=6x and the new equation becomes:

Now, we can get rid of the denominators, and we get:

So, x= 9
Now we know that Mr. Itol would take 9 hours to complete the task if he were to do it himself. To find how long it would take his assistant to complete the same task by himself, we just need to plug in the x-value into 2x:

Therefore, your answer is that Mr. Itol would take 9 hours to do the job alone, while his assistant will take 18 hours (double the time) to do the job alone.
Hope this helps :)
Assume that the length of the rectangle is "l" and that the width is "w".
We are given that:
(1) The length is one more than twice the base. This means that:
l = 2w + 1 .......> equation I
(2) The perimeter is 92 cm. This means that:
92 = 2(l+w) ...........> equation II
Substitute with equation I in equation II to get the width as follows:
92 = 2(l+w)
92 = 2(2w+1+w)
92/2 = 3w + 1
46 = 3w + 1
3w = 46-1 = 45
w = 45/3
w = 15
Substitute with w in equation I to get the length as follows:
l = 2w + 1
l = 2(15) + 1
l = 30 + 1 = 31
Based on the above calculations:
length of base = 31 cm
width of base = 15 cm