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:
Step-by-step explanation:
(4/5)n = (2/3)
move 4/5 to the right
n = (2/3)/(4/5)
n = 5/6
K = s + 4
k + s = 26
s + 4 = 26
Subtract 4 from both sides of the equation.
s = 22
Steve ran 22 miles.
after solving 
we get 
Step-by-step explanation:
We need to find the value of x in:
Solving:
So, after solving we get
Keywords: Solving the expression
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