Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Percentage Growth and Decay

No description
by

Mr Mattock

on 13 September 2018

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Percentage Growth and Decay

Percentage Growth and Decay
Starter
Starting with 100%, what percentage do you have if the original is:

(a) increased by 20%?
(b) decreased by 20%?
(c) increased by 2%?
(d) decreased by 2%?
(e) increased by 0.2%?
(f) decreased by 0.2%?
Activity
Complete the percentage growth and decay worksheet.
Percentage growth and decay
The value of a car depreciates by 20% every year. If the car is £39999 brand new, work out the value of the car after 5 years.
L.O. - To calculate growth and decay given as a percentage change.
Starter
Starting with 100%, what percentage do you have if the original is:

(a) increased by 20%?
120%
(b) decreased by 20%?
80%
(c) increased by 2%?
102%
(d) decreased by 2%?
98%
(e) increased by 0.2%?
100.2%
(f) decreased by 0.2%?
99.8%
Percentage growth and decay
The value of a car depreciates by 20% every year. If the car is £39999 brand new, work out the value of the car after 5 years.
39999 x 0.8 = £13106.87
5
Percentage growth and decay
The value of an antique increases by 4.6% every 5 years. Work out the total percentage increase of the antique over 100 years.
Percentage growth and decay
The value of an antique increases by 4.6% every 5 years. Work out the total percentage increase of the antique over 100 years.
100 x 1.046 = 245.83% of original so
145.83% increase.
20
Activity
Complete the percentage growth and decay worksheet.
1) $160.12
2) 43872 people
3) $361223.09
4) 500 x 0.88
2.37 x 10 mL

5) 51.2 mg
6) Approx 1.8 years
7) Approx 19 hours
8) Approx 29 days
n
-11
Plenary
Toby wants to buy a car.
A new car costs £15 450.
A different make of car that is two years old costs £10 500.
Each car depreciates in value by 20% per year.
He plans to sell the car when it is 7 years old.
Which car would be worth the most when he sells it?

Plenary
Toby wants to buy a car.
A new car costs £15 450.
A different make of car that is two years old costs £10 500.
Each car depreciates in value by 20% per year.
He plans to sell the car when it is 7 years old.
Which car would be worth the most when he sells it?
New car - 15450 x 0.8 = £3240.10
Used car - 10500 x 0.8 = £3440.64
Used car worth more.
7
5
Activities
Activity
Answers

Key
Examples

Worked
Example

Worked
Example

Bright Spark:
You have two vouchers for a restaurant, one that gives you 10% off, and one that gives you 20% off. Which order should you use them?

What about if the 20% off is only on the main course?
Full transcript