Answer:
n=10
Step-by-step explanation:
The given equation is
...(1)
Let nth term is 2n.
We need to find the values of n.
It is clear that
is sum of A.P., whose first term is 10 and common difference is 2.
Sum of A.P. is
where, a is first term and d is common difference.
Substitute a=10 and d=2 in the above formula.
...(2)
From (1) and (2), we get
Splitting middle term, we get
Since, n represents the number of terms so n cannot be a negative number, therefore number of term is 6.
Note: nth term and variable n both are different.
![a_n=a+(n-1)d](https://tex.z-dn.net/?f=a_n%3Da%2B%28n-1%29d)
![a_6=10+(6-1)2=10+10=20](https://tex.z-dn.net/?f=a_6%3D10%2B%286-1%292%3D10%2B10%3D20)
Sixth term is 20. So,
![2n=20](https://tex.z-dn.net/?f=2n%3D20)
![n=10](https://tex.z-dn.net/?f=n%3D10)
Therefore, the value of n is 10.
Answer:
10y
Step-by-step explanation:
Answer:
3.2
Step-by-step explanation:
The distance of 2.7 and 3.7 to 3.2 is .5 each, thus it is the integer in between both numbers.
Answer:
-13
Step-by-step explanation:
1: -6-(-7)
2: change the sign to get rid of the parenthesis so -6+-7
3: add the numbers and you get -13 because 6+7=13