1718 WH3X CH1 lesson 1

• Wiskunde
• Middelbare school
• havo
• Leerjaar 3

Welcome to Mathematics

Ms B.J.E. Mulders-Kunst (KUNB)
[e-mail]

At the start of each lesson

- Book, pencilcase, calculator, notebook on your desk
- Find the homework for that lesson in your notebook
- No earbuds/headphones, phones or other devices (if using an iPad with Studiekit: close all other apps)

Working in your notebook

See the "guidelines Mathematics" on Magister

Schedule

Maths in year 3

- Language and notation
- Choice at the end of the year: Maths A, Maths B or no Maths

Chapter 1: Exponential Growth

In this lesson you will learn:
- How to work in your notebook
- What a (growth)factor is
- How to convert a percental increase/decrease to a factor
- What the standard form of an exponential formula is
- How to find the initial amount and growth factor in a simple table or graph

Factor

A factor is the number by which you multiply an original amount to get a new amount.

Factor

a) Prices are increased by 15%, what factor do you use to calculate the new price from the old price?
b) Prices are decreased by 20%, what factor do you use to calculate the new price from the old price?

Factor

a) Prices are increased by 15%, what factor do you use to calculate the new price from the old price?

Factor = 1.15

Factor

b) Prices are decreased by 20%, what factor do you use to calculate the new price from the old price?

Factor = 0.8

Exponential formula

The standard form of an exponential formula is:
y and t are the variables
b is the initial amount
g is the growth factor

y=b⋅g​t​​

Exponential formula

The standard form of an exponential formula is:
y and t are the variables
b is the initial amount
g is the growth factor
The initial amount is the value of y when t = 0
The growth factor is the factor you multiply y with when t increases by 1

y=b⋅g​t​​

Exponential formula

Give the formula for the table below

y=b⋅g​t​​

Exponential formula

Give the formula for the table below



Initial amount (b) = 250
Growth factor = 0.8

y=b⋅g​t​​

y=250⋅0.8​t​​

​250​​200​​=0.8

​200​​160​​=0.8

​160​​128​​=0.8

Homework

- Read the guidlines Mathematics on Magister
- Make exercises R1, R2, R5, R6, R7 on pages 8 and 9
- Correct your homework with the solutionsbook (page 6)