Answer:
585 and 54
Step-by-step explanation:
Calculate the mean of each data set below. Can you find any shortcuts that allow you to find the mean without having to do much calculation? Homework help 6, 10, 6, 10 11, 12, 12, 13, 12 0, 5, 4, 8, 0, 7
Answer: To find the mean of the given observations. we just need to first find the sum of the given observations and the divide the calculate sum by the total number of observations.
So here:
Sum of of observations 
Number of observations = 15
Therefore, the mean 
If a = first term and r = common ratio we have
a + ar + ar^2 = 13 and ar^2 / a = r^2 = 9
so r = 3
and a + 3a + 9a = 13
so a = 1
so they are 1,3 and 9
2.
in geometric series we have
4 , 4r ,4r^2 , 60
Arithmetic;
4, 4r , 4r + d , 4r + 2d
so we have the system of equations
4r + 2d = 60
4r^2 = 4r + d
From first equation
2r + d = 30
so d = 30 - 2r
Substitute for d in second equation:-
4r^2 - 4r - (30-2r) = 0
4r^2 - 2r - 30 =0
2r^2 - r - 15 = 0
(r - 3)(2r + 5) = 0
r = 3 or -2.5
r must be positive so its = 3
and d = 30 - 2(3) = 24
and the numbers are 4*3 = 12 , 4*3^2 = 36
first 3 are 4 , 12 and 36 ( in geometric)
and last 3 are 12, 36 and 60 ( in arithmetic)
The 2 numbers we ause are 12 and 36.
Answer:
1)Area; A = ¼πr²
Perimeter; P = πr/2 + 2r
2)A = 19.63 cm²
P = 17.85 cm
3) r = 8.885 cm
4) r = 14 cm
Step-by-step explanation:
This is a quadrant of a circle. Thus;
Area of a circle is πr². A quadrant is a quarter of a circle. Thus;
Formula for Quadrant Area is; A = ¼πr²
A) Perimeter of a circle is 2πr. Thus, perimeter of a quadrant is a quarter of the full circle perimeter.
Formula for the quadrant perimeter in the image given is;
P = 2πr/4 + 2r
P = πr/2 + 2r
B) When r is 5 cm;
A = ¼π(5)²
A = 19.63 cm²
P = π(5)/2 + 2(5)
P = 17.85 cm
C) when A is 100cm²:
¼πr² = 100
r² = 100 × 4/π
r² = 78.9358
r = √78.9358
r = 8.885 cm
D) when P = 50 cm.
50 = πr/2 + 2r
50 = (½π + 2)r
r = 50/(½π + 2)
r = 14 cm
Answer:
k = 18
Step-by-step explanation:
Given that y varies inversely as x then the equation relating them is
y =
← k is the constant of variation
To find k use the condition y = 3 when x = 6, that is
3 =
( multiply both sides by 6 )
18 = k
The constant of variation is k = 18