Solution:
(12, 18, 24, 30…… 60)
T1 = 12, T2 = 18, T3=24, T4 = 30, Tn = 60
T2 – T1 = T3 – T2
18 – 12 = 24 – 18 6 = 6
This above is arithemetic sequence.
Common difference (d) = 6
First term (a) = 12 Tn = a + (n – 1) d
60 = 12 + (n – 1) 6
60 = 12 + 6n – 6
60 = 6n + 6 n = 9
*The week that I can jog 60 minutes in a day is ninth weeks. Therefore, it would be eight weeks before I am up to jogging 60 minutes per day.
ii. A culture of bacteria doubles every 2 hours. If there are 500 bacteria at the beginning, how many bacteria will there be after 24 hours?
Solution:
500, 1000, 2000, 4000……
Start 2hours, 4hours, 6hours
T1 = 2, T 2 = 4, T3=6 T1 = 500, T2 = 1000, T3= 2000, T4 = 4000
T2 – T1 = T3 – T2 T2T1=T3T2 4 – 2 = 6 – 4 1000500=20001000 2 = 2 2 = 2
This above is arithemetic sequence. This above is geometric sequence.
Common difference (d) = 2 Common ratio (r) = 2
First term (a) = 2 First term (a) = 500
Tn = 24 Tn = 12
Tn = a + (n – 1) d Tn = arn-1 24 = 2 + (n – 1) 2 T12 = 500(2)12-1
24 = 2 + 2n – 2 T12 = 500(2)11
2n = 24 – 2 + 2 T12 = 500 × 2048
2n = 24 T12 = 1024 000 n = 12
Therefore, if there are 500 bacteria at the beginning, 1024 000 bacteria will there be after 24 hours.
Task 2 i. What is the different between trade discount and cash discount? * Trade discounts are payments to distribution channel members for performing some function. For example if Sara had a warehouse, stocked my goods in