Answer:
(a) Y = 129.3x (b) It is an estimate as it may not be a true reflection of a student's height
Step-by-step explanation:
(a) Estimate of the mean height is the sum of the heights of all the students divided by the total number of students.
The question however needs more information for its estimation as 129.3cm is representative and may be the mean height but it was not stated.
However, assuming it is the mean height,
Let the total number of students be x
while Y is the sum of all individual student heights
Mathematically, mean = Y/x
Therefore 129.3 = Y/ x
implying that Y = 129.3x
(b) It is an estimate because computation of the mean gives an average which may not be an exact value. For example, the mean here is 129.3 whereas there will be many heights greater than that and some lesser than that and obviously, there may be no student with height of 129.3 hence it is an estimate.
We can see from the diagram that the length of the rectangle is 2 lots of the radius of one quarter circle. The width is made up of one radius, therefore the width is half of the length.
This means that the width of the rectangle is 9cm, and the radius of each quarter circle is 9cm.
To find the shaded area, we find the area of the rectangle and subtract from the areas of each circle, which are equal:
A = lw - 1/2(pi x r^2)
A = 9 x 18 - 1/2(81pi)
A = 162 - 81/2 pi
A = 34.8cm (3sf)
No they cannot be simplified together from what I know
Answer: $754.94
Step-by-step explanation:
Just took the quiz got 100%
Let x represent the cost of the movie ticket and y represent the cost of a snack item.
3x + 3y