Ratios/Rates/Unit Rates
Write as a ratio in 3 ways if there are 15 dogs and 18 cats.
cats to dogs
18/15
18:15
18 to 15
Proportion?
35/16 5/2
State cross products.
70, 80 no
Actual 20 ft
Scale?
1/10
How do you find slope from a graph?
rise/run
Direct variation? Explain.
y = 9x
Write as a rate and a unit rate.
5 games for $475
$475/5 games = $95/1 game
Do the rates form a proportion?
10 books for $125; $572 for 52 books
State cross products.
6500; 5720 no
A toy measures 2.5 inches and the actual measures 25 feet. What is the scale?
1/10
Find the slope from the graph shown.
2
Direct variation? Explain. If so, find k.
4y = 2
Yes, y = kx form
k = 1/2
Which is a better buy? Tell what each equal
$9.16 for 0.4 m
OR
0.6 m for $13.20
$22.90/1 m
$22/1 m
first is better
Find x:
28/9 = 19.6/x
6.3
Scale is 1:25. The actual is 300. What is the model?
12
Find the slope from the graph shown.
2/3
3 things a graph needs to have to be in direct variation
straight line
same slope
goes through origin
You earn $27 for 6 chores. Your friend earns $36 for 8 chores. Find each of your pay rates and tell whether they are the same or not.
$4.50/1 chore
$4.50/1 chore
Yes, same pay rate
9 eggs
On a map, the scale is 2:37.5 If the map has a 8 measurement, what is the actual?
150
Find the slope between (8, -2) (9, 7)
9
Plot the data on a graph. Then tell whether it is in direct variation and why.
(0, 0) (4, 5) (8, 10) (10, 12)
No, not same slope
You run 600 yards in 2 minutes and 5 seconds. What is your average speed?
4.8 yd/1 sec
8 oranges cost $1.00. How many will 9.5 dozen cost?
$14.25
5.5 ft
Find the slope between (-12, -3) (-4, 19)
11/4
Make a graph of the data and then write the equation of the line.
(2, 10) (8, 40) (10, 50)
y = 5x