Given:
First term of an arithmetic sequence is 2.
Sum of first 15 terms = 292.5
To find:
The common difference.
Solution:
We have,
First term: 
Sum of first 15 terms: 
The formula of sum of first n terms of an AP is
![S_n=\dfrac{n}{2}[2a+(n-1)d]](https://tex.z-dn.net/?f=S_n%3D%5Cdfrac%7Bn%7D%7B2%7D%5B2a%2B%28n-1%29d%5D)
Where, a is first term and d is common difference.
Putting , n=15 and a=2 in the above formula, we get
![292.5=\dfrac{15}{2}[2(2)+(15-1)d]](https://tex.z-dn.net/?f=292.5%3D%5Cdfrac%7B15%7D%7B2%7D%5B2%282%29%2B%2815-1%29d%5D)
![292.5=\dfrac{15}{2}[4+14d]](https://tex.z-dn.net/?f=292.5%3D%5Cdfrac%7B15%7D%7B2%7D%5B4%2B14d%5D)
![292.5=15[2+7d]](https://tex.z-dn.net/?f=292.5%3D15%5B2%2B7d%5D)
Divide both sides by 15.
Dividing both sides by 7, we get
Therefore, the common difference is 2.5.
Answer:
B is a statistical question
Step-by-step explanation:
A and C ask for qualitative data or categorical data
B asks for quantitative data or numerical data
We obviously use numerical data for statistical work, so B is the answer
jonas wants to mail a package that weighs 4.2 kilogram. how much dose the package weigh in pounds?
we know that
1 kg = 2.20462262185 lb
1 kg=2.2 lb
we have
4.2 kg
Convert to pounds
so
4.2 kg=4.2*(2.2)=9.24 pounds
therefore
the answer is 9.24 pounds
Let's make the width 'x'.
And the length 'x+4'.
Perimeter is adding up ALL the sides.
Add: x + x + 4 + x + x + 4.
Simplify:
x + x + 4 + x + x + 4 = 4x + 8
a(1) = 3(1)-1 = 3-1 = 2
a(2) = 3(2)-1 = 6-1 = 5
a(3) = 3(3)-1 = 9-1 = 8
So, the sequence would be 2,5,8,11....
