The answer if you are looking for it this way.2.23
Answer:
Although the notation is sloppy, I will assume based on former questions of the same that "∑n=15[5(−2)^n−1]" translates mathematically to . Please correct me, though, if this in incorrect.
Anyway, there is neat formula that will deal with question very quickly. It is the following:
Sn is the sum of the geometric series
a1 is the first term in the series
r is the common ratio
n is the number of terms in the finite geometric series
Let's use this formula to our advantage! However, there are two variables that we do not know: a1 and n. Let's start with a1.The first term in the series is when n=1, so let's determine what that is.
It should be noted that 24 percent of 60 is 14.4.
<h3>How to calculate the percentage?</h3>
The question is to calculate 24% of 60.
This will go thus:
= 24% × 60
= 24/100 × 60
= 0.24 × 60
= 14.4
Therefore, 24% of 60 is 14.4.
Learn more about percentages on:
brainly.com/question/24877689
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The air force plane travelled for a total of 6.9 hours.
<u>SOLUTION:
</u>
Given, An Air Force plane left Nairobi and flew west at an average speed of 159 mph. A cargo plane left sometime later flying in the same direction at an average speed of 207 mph. After flying for 5.3 hours the cargo plane caught up with the Air Force plane.
We have to find the number of hours the Air Force plane flew before the cargo plane caught up.
Now, we know that, 
For air force plane 
Now, when cargo plane caught the air force plane the distance travelled by the planes will be equal.
So, 
Time taken by air force plane = 6.9 hrs
