Answer: an=8+(n-1)(-6) .
Step-by-step explanation:
Answer:
8428
Step-by-step explanation:
According to the Question,
- Given, A theater has 56 rows of seats. If there are 13 seats in the first row, 18 in the 2nd row, 23 in the 3rd row.
We have a number sequence 13, 18, 23, ...
- We can say that this is an arithmetic sequence because of the common difference 'd', is equal to 5, and the first term 'a1' is equal to 13.
- The formula for the sum of an arithmetic sequence with n terms is given is .
Substitute the given values into the equation to solve for the sum of the 56 rows of seats.
Therefore, there are 8428 seats in all.
Answer:
62.8
Step-by-step explanation:
The formula for circumference is 2(pi)r
Let's plug in the values.
Well, we know the diameter, and since the radius is 1/2 the diameter, but then you multiply by 2 again, you don't have to change anything. Therefore, another formula is (pi)<em>d</em>
3.14 x 20
= 62.8 is your answer. And the answer is already rounded to the nearest tenth, so nothing is left to do!
<em>Hope this helps!</em>