Answer: Choice A
S9 = (9/2)*(2+26)
===============================================
The formula is
Sn = (n/2)*(a1+an)
where
Sn = sum of the first n terms (nth partial sum)
n = number of terms
a1 = first term
an = nth term
In this case,
n = 9
a1 = 2 (plug in n = 1 into the formula an = 3n-1 and simplify)
an = a9 = 26 (plug n = 9 into the formula an = 3n-1 and simplify)
So,
Sn = (n/2)*(a1+an)
S9 = (9/2)*(2+26)
will help us find the sum of the first 9 terms of this arithmetic sequence
Answer:it’s A
Step-by-step explanation:
Answer:
I belive the answer is 21.42% :)
Answer:
3000 books
Step-by-step explanation:
We know the author receives a one time fee of $2500. On top of that, the author will receive $1.50 per book sold. This is a constant rate and is linear because of this. We can use y=mx+b. M is the slope or rate of change. M here is $1.50. B is the starting value which is $2500 here.
We write y=1.5x+2500.
This equation will give the amount of money the author earns for x number of books sold. If y=7000 for the author earning 7000. We will use inverse operations to isolate and find x.
7000=1.5x+2500
7000-2500=1.5x+2500-2500
4500=1.5x
4500/1.5=x
3000=x
Answer:
$0.90
Step-by-step explanation:
3 dozen = 36
0.4 × y = 36 × 0.1
0.4y = 3.6
0.4y ÷ 0.4 = 3.6 ÷ 0.4
y = 9
