Answer:
The width of the building is 50 lamps and 60 lamps will be needed.
Step-by-step explanation:
The perimeter is computed by the sum of the sides of the building, since the length and width are equal on the oposite sides of the building, the perimeter is given by:
perimeter = 2*length + 2*width
900 = 2*(400) + 2*width
2*width + 800 = 900
2*width = 900 - 800
2*width = 100
width = 100/2 = 50 feets
To know how many lights bulbs will be needed we need to take the perimeter of the building and divide it by the space between the lamps. We have:
number o lamps = 900/15 = 60 lamps
Answer:
1/6a-1/6
Step-by-step explanation:
-2/3 transferred into 6th's is -4/6. You combine like terms, -4/6a+5/6a=1/6a
Then since -1/6 doesn't have a like term, it stays the same.
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
![S_n= \frac{n}{2} [2a_1+(n-1)d]S](https://tex.z-dn.net/?f=S_n%3D%20%5Cfrac%7Bn%7D%7B2%7D%20%5B2a_1%2B%28n-1%29d%5DS)
.
Substitute the given values into the equation to solve for the sum of the 56 rows of seats.
![S_56= \frac{56}{2}[2(13)+(56-1)(5)]\\S_{56}=28\left[26+275\right]\\S_{56}=28\left[301\right]\\S_{56}=8428](https://tex.z-dn.net/?f=S_56%3D%20%5Cfrac%7B56%7D%7B2%7D%5B2%2813%29%2B%2856-1%29%285%29%5D%5C%5CS_%7B56%7D%3D28%5Cleft%5B26%2B275%5Cright%5D%5C%5CS_%7B56%7D%3D28%5Cleft%5B301%5Cright%5D%5C%5CS_%7B56%7D%3D8428)
Therefore, there are 8428 seats in all.
First, you add up the total number of students because we would base our percentage one this.
Total number of students = 1+4+5+10+20+10+5
Total number of students = 55
Now, let's count how many of them got a score of more than 70. For this, you would only count the students belonging to 70-under 80, 80-under 90 and 90-under 100.
Students who got more than 70 = 20+ 10 + 5 = 35
Therefore the percentage is equal to:
Percentage = 35/55 * 100 = 63.64%
