Answer: 2343 / 256
Explanation
I will do this for you in two forms: 1) adding each term, and 2) using the general formula for the sum of geometric series.
1) Adding the terms:
4
∑ 3 (3/4)^i = 3 (3/4)^0 + 3 (3/4)^1 + 3 (3/4)^2 + 3 (3/4)^3 + 3 (3/4)^4
i=0
= 3 + 9/4 + 27/16 + 81/64 + 243/256 = [256*3 + 27*16 + 64*9 + 4*81 + 243] / 256 =
= 2343 / 256
2) Using the formula:
n-1
∑ A (r^i) = A [1 - r^(n) ] / [ 1 - r]
i=0
Here n - 1 = 4 => n = 5
r = 3/4
A = 3
Therefore the sum is 3 [ 1 - (3/4)^5 ] / [ 1 - (3/4) ] =
= 3 [ 1 - (3^5) / (4^5) ] / [ 1/4 ] = 3 { [ (4^5) - (3^5) ] / (4^5) } / {1/4} =
= (3 * 781) / (4^5) / (1/4) = 3 * 781 / (4^4) = 2343 / 256
So, no doubt, the answer is 2343 / 256
The language art teacher wants to know the opinion of the ENTIRE school, so it would be fair if the teacher takes a sample from the ENTIRE school population. She can use the stratified sampling method where she can take a proportionate sample from each grade.
Correct answer: All students in each grade
The difference is 3ft since the surface area for the prism is 57, and the surface area for the cube is 54.
You can use the surface area formula
2(wl+hl+hw) = Area
2·(3·4.5+2·4.5+2·3)=57
And a cubes surface area formula
6a^2 = Area
6·32=54
Answer:
x = 4
Step-by-step explanation:
Given
= 5 ( multiply both sides by 3 to clear the fraction )
7 + 2x = 15 ( subtract 7 from both sides )
2x = 8 ( divide both sides by 2 )
x = 4
