Add three consecutive letters of the alphabet to the group of
letters below, without splitting the consecutive letters, to form
another word. DY
Slide 2
STUDY
Slide 3
Which month comes next? January, March, June, October, March,
?
Slide 4
September
Slide 5
All widgets are green. Everything green has a hole in the
middle. Some things that are green have a jagged edge. Therefore:
1. All widgets have a hole in the middle 2. Everything with a
jagged edge is a widget. 3. Neither of the above is true. 4. Both
the above are true.
Slide 6
1. All widgets have a hole in the middle
Slide 7
Week 2
Slide 8
Your sister is selling Girl Scout cookies for $2.60 a box. Shes
already made $15.60. Write an equation for the situation above: y =
2.60x + 15.60 How much does she make after selling 10 more boxes? y
= 2.60 (10) + 15.60 = $41.60
Slide 9
How many boxes does she have to sell to make $130? (y = 2.60x +
15.60) 130 = 2.60x + 15.60 (subtract 15.60 from both sides) 114.40
= 2.6x (divide both sides by 2.6) x = 44
Slide 10
y=5x-9 Solve for y when x = 2. y = 5(2)-9 y = 1 Solve for x
when y = 6. 6 = 5x 9 (next: add 9 to both sides) 15 = 5x (next:
divide both sides by 5) x = 3
Slide 11
We learned about linear modeling. Model: y = mx +b Graph:
straight line
Slide 12
Exponential Modeling x is an exponent.
Slide 13
EXPONENTIAL GROWTHEXPONENTIAL DECAY Model: y = a(1+r) x y:
final a: initial r: rate x: time Model: y = a(1-r) x y: final a:
initial r: rate x: time
Slide 14
Graph:
Slide 15
Populations tend to growth exponentially not linearly When an
object cools (e.g., a pot of soup), the temperature decreases
exponentially toward the ambient temperature (the surrounding
temperature) Radioactive substances decay exponentially Bacteria
populations grow exponentially Money in a savings account with at a
fixed rate of interest increases exponentially Viruses and even
rumors tend to spread exponentially through a population (at first)
Anything that doubles, triples, halves over a certain amount of
time Anything that increases or decreases by a percent
Slide 16
Difference: Linear: Constant Rate of Change Exponential:
Constant Percent Change How can you tell? Linear, if it increases
by the same or decreases by the same Exponential, calculate the
percent change and see if it stays constant Percent change =
(changed- reference)/reference
Slide 17
exponential growth?
Slide 18
Slide 19
Slide 20
The percent change is 20% each time. So it is an exponential
function.
Slide 21
Two bosses A: one million dollars for one month B: a penny
doubled every day for a month Who would you work for?
Slide 22
Boss B Day 1: $.02 Day 2: $.04 Day 3: $.08 Day 10: $10.24 Day
20: $10,485.76 Change of mind?
Slide 23
Calculations y = a (1+r) x y =.01 (1+1) 30 y =
10,737,418.24
Slide 24
Growth (savings account) y = a(1+r) x Decay (radioisotope
dating) y = a(1-r) x
Slide 25
If roaches grow at a rate of 25% every 10 days, how long will
it take 400 roaches to become 1000 in number?
Slide 26
Slide 27
Slide 28
Drag it down Right click on the + at the right bottom Move down
with the mouse
Slide 29
Slide 30
A little bit after 40 days
Slide 31
Dead Sea Scrolls have about 78% of the normally occurring
amount of Carbon 14 in them. Carbon 14 decays at a rate of about
1.202% per 100 years. How old are the Dead Sea Scrolls?
Slide 32
Since we know the rate of decay per every 100 years, make the
excel table have intervals of 100 years. (after entering 0 and 100,
you can select the two and drag down)
