Geometric Sequences - Project Maths

Teaching & Learning Plan: Geometric Sequences
Section A: Student Activity 1
1. Nigel saves €2 in the first week of the New Year, if he doubles the amount he
saves every week after that, how much will he save in the 2 nd , 3 rd , 4 th and 5 th
week of the year
a. Complete the following table and explain your reasoning:
Week No. 1 st Week 2 nd Week 3 rd Week 4 th Week 5 th Week
Amount Saved
2. The price of an item trebles on the first day of every month. It costs €2.00 on
the 1 st January, calculate its cost on the first day of the following four months
a. Complete the following table and explain how you got your calculations:
Date 1 st February 1 st March 1 st April 1 st May
Cost
3. A town had a population of 100. In January 2010, A new factory was being
built in the town and consequently, the local authority expected that the
town’s population would increase by 20% year-on-year for the next 5 years.
a. Explain clearly how the town’s population in January 2011 is calculated
b. Complete the following table and explain your reasoning:
Date January 2011 January 2012 January 2013 January 2014 January 2015
Population
4. Examine the completed tables from the previous three questions.
a. Do the numbers you calculated follow any particular pattern in each table
b. Can you generate a formula to calculate the entries in each of the tables
5. Assuming the patterns in Questions 1 and 2 (above) continue, complete the
table below. It is not necessary to evaluate the powers.
Question 1 Amount saved in the 50th month Amount saved in the 100th month
Question 2 Population in January 2020 Population in January 2040
For question 1 above what does T 50 mean
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