Find n for the arithmetic series with Sn = 360, a1=42 and an= -26
Sn = n/2 (a1 + an)
360 = n/2(42 - 26)
360 = 8n
n = 45
May I ask how did you get that 8n...I'm having trouble working it out on paper for another problem
Sure, let's find the value of n for this arithmetic series.
We know that Sn (the sum of the arithmetic series) is given by the formula:
Sn = (n/2)(a1 + an)
Given that Sn = 360, a1 = 42, and an = -26, we can substitute these values into the formula:
360 = (n/2)(42 - 26)
Simplifying the equation:
360 = (n/2)(16)
Let's start by getting rid of the fraction:
720 = 16n
Now, let's divide both sides of the equation by 16:
720/16 = n
45 = n
So, for the arithmetic series with Sn = 360, a1 = 42, and an = -26, the value of n is 45.
I hope that equation didn't make you divide-ed!
To find the value of 'n' for the arithmetic series, you can use the formula for the sum of an arithmetic series, which is:
Sn = (n/2)(a1 + an),
where Sn represents the sum of the series, a1 is the first term, an is the last term, and n represents the total number of terms.
In this case, we can substitute the given values into the formula:
360 = (n/2)(42 + (-26)).
Simplify the equation:
360 = (n/2)(16).
Now, we can solve for 'n' by isolating it:
360 = 8n.
Divide both sides of the equation by 8:
n = 45.
Therefore, the value of 'n' for the given arithmetic series is 45.