Answer:
Option A. 5
Step-by-step explanation:
From the question given above, the following data were obtained:
First term (a) = –3
Common ratio (r) = 6
Sum of series (Sₙ) = –4665
Number of term (n) =?
The number of terms in the series can be obtained as follow:
Sₙ = a[rⁿ – 1] / r – 1
–4665 = –3[6ⁿ – 1] / 6 – 1
–4665 = –3[6ⁿ – 1] / 5
Cross multiply
–4665 × 5 = –3[6ⁿ – 1]
–23325 = –3[6ⁿ – 1]
Divide both side by –3
–23325 / –3 = 6ⁿ – 1
7775 = 6ⁿ – 1
Collect like terms
7775 + 1 = 6ⁿ
7776 = 6ⁿ
Express 7776 in index form with 6 as the base
6⁵ = 6ⁿ
n = 5
Thus, the number of terms in the geometric series is 5.
Answer: she needs to save $6510
Step-by-step explanation:
In the first year, she expects her total cost to be $9,850. Wei has already saved $1,220 for college. This means that the remaining amount that she needs would be
9850 - 1220 = $8630
she expects to receive grants and scholarships that total $2,120. Therefore, the amount of money that she should save to be able to pay for her first year of college would be 8630 - 2120 = $6510
Answer:
{(12-4) + (15-8)}x = 65
Step-by-step explanation:
The amount Amber earns per week
12-4
The amount Nathan earns per week
15 -8
The total amount per week they earn together
(12-4) + (15-8)
Multiply by x weeks
{(12-4) + (15-8)}x
Set this equal to 65 to be the amount they need to equal 65 dollars
{(12-4) + (15-8)}x = 65