Answer:
is it radius or diameter?
Answer:
62.4 cm³
Step-by-step explanation:
Hope this helps :)
This is a geometric sequence with first term 1 and common ratio -1/2. r=-1/2.
a(n) = a(1)*(r)^(n-1).
Check: If n=2 our formula must return -1/2. Does it?
a(2) = 1(-1/2)^(2-1) = (-1/2)^1 = - 1/2. Yes.
a(3) should be 1/4. Is it? a(3) = (-1/2)^(3-1) = 1/4 Yes.
Then a(8) = (-1/2)^(8-1) = (-1/2)^7 = -1 / 2^7 = -1/128 (answer)
Answer:
85, 68, 51
Step-by-step explanation:
Average: The sum of all the numbers divided by the number of numbers
If the ratio of the scores is 5 : 4 : 3, let's just set it as 5x : 4x : 3x
Then using the definition of an average, we can write this equation.
(5x + 4x + 3x) / 3 = 68
Multiply both sides by 3.
5x + 4x + 3x = 68 * 3
Simplify.
12x = 204
x = 17
Now, substitute x = 17 into the original scores (5x, 4x, and 3x)
5x = 5 * 17 = 85
4x = 4 * 17 = 68
3x = 3 * 17 = 51
Just in case, let's check this answer. Find the average of the 3 test scores.
(85 + 68 + 51) / 3 =
204 / 3 = 68
Thus, the answers are correct
