Answer:
12
Step-by-step explanation:
To find the mean of a set of numbers, add all the numbers together. Then, divide the sum by how many numbers you had to begin with.
Add the numbers together:
10 + 12 + 15 + 11
= 48 This is the sum of the data
Count how many numbers you had:
10, 12, 15 and 11 are FOUR numbers (amount of data).
Divide the sum of the data by the amount of data.
48 ÷ 4 = 12 This is the mean
The mean of 10, 12, 15, 11 is 12.
(6x + 30)+(2x+6)= 180
8x +36= 180
8x= 144
X= 18
So 2x+6 = 42
And 6x+30 = 138
The patch doubles in size each day so, on the 47th will be half the size than on the 48th day
Large sphere's radius = R,
small sphere's radius = r, R = 8r
surface area of a sphere (SA) = 4×pi×radius^2
So what we need is the SA of the larger in terms of the smaller sphere, so if:
SA (of R) = 4×pi×R^2, then plug in "8r" for "R"...
SA = 4×pi×(8r)^2 = 4×3.14×64r^2
SA = 12.57×64r^2 = 804 r^2
Therefore the SA of the larger sphere is 804 times the SA of the smaller sphere.
I hope that makes sense!
By using different math operations
