Question

PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!! What is (3n - 2) equal to?

Answer 1

Answer: 925

Step-by-step explanation:

First, we need to find the first term (a₁) and the last term (a₂₅):

$a_n=3n-2\\\\a_1=3(1)-2\\.\quad =3-2\\.\quad =1\\\\a_{25}=3(25)-2\\.\quad = 75-2\\.\quad = 73$

Now we can input the information above into the Sum formula:

$S_n=\dfrac{a_1+a_n}{2}\times n\\\\S_{25}=\dfrac{a_1+a_{25}}{2}\time 25\\\\.\quad =\dfrac{1+73}{2}\times 25\\\\.\quad =\dfrac{74}{2}\times 25\\\\.\quad =37\times 25\\\\.\quad =925$