Maths lesson 6
Exponential Growth and Decay
Growth and decay
- Formula: Original x Multiplier ⁿ
Water bodies typically support a large number of different plants, however if they become
polluted the number of organisms they support are decreased by 30% each month. If a lake has
15 000 organisms, how many after 6 months.
15000 x 0.76
= 1764.7
= 1760
Newton has 23 000
Population decreases at 1.4% a year
Calculate population after 5 years
(100-1.4) / 100
= 0.986
23 000 x 0.9865
= 21434.45329
= 21400
Inequalities
I
, Sets and Venn Diagrams
- Sets = collection of items
- Element = an time in a set
n(P) - P is the number of elements in the set
Venn diagram is drawn as a square to represent the Universal set.
All other sets are drawn as circles.
Subsets vs Proper sets
Proper subsets do not have all the elements of the original set.
X’ - the apostrophe means everything that's not in X
Exponential Growth and Decay
Growth and decay
- Formula: Original x Multiplier ⁿ
Water bodies typically support a large number of different plants, however if they become
polluted the number of organisms they support are decreased by 30% each month. If a lake has
15 000 organisms, how many after 6 months.
15000 x 0.76
= 1764.7
= 1760
Newton has 23 000
Population decreases at 1.4% a year
Calculate population after 5 years
(100-1.4) / 100
= 0.986
23 000 x 0.9865
= 21434.45329
= 21400
Inequalities
I
, Sets and Venn Diagrams
- Sets = collection of items
- Element = an time in a set
n(P) - P is the number of elements in the set
Venn diagram is drawn as a square to represent the Universal set.
All other sets are drawn as circles.
Subsets vs Proper sets
Proper subsets do not have all the elements of the original set.
X’ - the apostrophe means everything that's not in X
