A study conducted by TeleCable estimates that the number of cable TV subscribers will grow at the rate of new subscribers/month t months from the start date of the service. If 6,000 subscribers signed up for the service before the starting date, how many subscribers will there be 16 months from that date?
A) 28,994 subscribers
B) 28,386 subscribers
C) 28,720 subscribers
D) 28,831 subscribers

Question

A study conducted by TeleCable estimates that the number of cable TV subscribers will grow at the rate of  new subscribers/month t months from the start date of the service. If 6,000 subscribers signed up for the service before the starting date, how many subscribers will there be 16 months from that date?
A) 28,994 subscribers 
B) 28,386 subscribers 
C) 28,720 subscribers 
D) 28,831 subscribers

Quizplus · Accepted Answer

Using the formula for arithmetic sequence:

tn = a + (n-1)d,

where
tn = number of subscribers after n months,
a = initial number of subscribers (6,000),
d = rate of growth (11eaa8b1_dad0_8db0_b1b6_27c9de9fb372_TB6026_11),
n = number of months (16),

we can compute for the number of subscribers:

tn = 6000 + (16-1)(11eaa8b1_dad0_8db0_b1b6_27c9de9fb372_TB6026_11)
tn = 6000 + 165(11eaa8b1_dad0_8db0_b1b6_27c9de9fb372_TB6026_11)
tn = 28,720

Therefore, there will be 28,720 subscribers 16 months from the starting date. The best choice is C.

A Study Conducted by TeleCable Estimates That the Number of Cable