Help pls help NOW! 35 points.
1 answer:
You might be interested in
Given:
The geometric sequence is:
1 -4
2 20
3 -100
To find:
The explicit formula and list any restrictions to the domain.
Solution:
The explicit formula of a geometric sequence is:
...(i)
Where, a is the first term, r is the common ratio and .
In the given sequence the first term is -4 and the second term is 20, so the common ratio is:
Putting in (i), we get
where
Therefore, the correct option is B.
We know that our bag has n white tiles and 5 black tiles.
So, the total number of tiles in the bag is n + 5.
We know that a tile is drawn at random and is replaced, then a second tile is drawn.
a) We want to find the probability that the first tile is white.
Because all the tiles have the same probability of being randomly drawn, the probability of drawing a white tile is just the quotient between the number of white tiles and the total number of tiles in the bag.
And for the second draw, we do not have any restrictions, so the probability is the above one.
b) Now we want both tiles to be white.
For the first one we already know the probability, which is:
And because the tile is replaced, the probability of drawing a white tile again is exactly the same:
The joint probability (the probability of both of these outcomes to happen together) is the product of the individual probabilities.
Probability =
If you want to read more about probability, you can read: