Answer:

Step-by-step explanation:
The first step to solving this problem is verifying if this sequence is an arithmetic sequence or a geometric sequence.
This sequence is arithmetic if:

We have that:




This is not an arithmetic sequence.
This sequence is geometric if:




This is a geometric sequence, in which:
The first term is 40, so 
The common ratio is
, so
.
We have that:

The 10th term is
. So:



Simplifying by 4, we have:

Let B be the event that Andrea passes her test, and let A be the event
<span>that she studies. We are given that P(A and B) = 17/20, and that P(A) = 15/16. </span>
<span>Now the probability that Andrea passes her test given that she has studied </span>
<span>is represented by P(BlA). The formula your teacher gave you can be written as </span>
<span>P(BlA) = P(A and B) / P(A). </span>
<span>So P(BlA) = P(A and B) / P(A) = (17/20) / (15/16) = (17/20)*(16/15) = 68/75.</span>
Answer:
Step-by-step explanation:
For species A,

For species B,

When their populations are equal,

The diagram below shows the population of Species A overtaking that of Species B in about 30.5 yr.
The answer is principal.
Hope this helped c: