Ratios and Proportions
What is the constant of proportionality from these ordered pairs: (2,6), (4,12), (6,18)?
3
What is 20% of 50?
10
Simplify: 3x + 5x
8x
Mean of: 2, 4, 6, 8
5
Probability of flipping heads
1/2
Is this proportional? y = 5x + 2
No
A $40 shirt is 25% off. What is the discount amount?
$10
Solve: x + 7 = 15
x=8
Median of: 3, 5, 7, 9, 11
7
Probability of rolling a 3 on a die
1/6
If 3 notebooks cost $6, how much do 10 notebooks cost?
$20
Final price of a $60 item after 20% discount
$48
Solve: 2x = 18
x=9
Range of: 10, 15, 20, 25
15
Experimental vs theoretical probability difference
Theoretical: expected; "what could happen"
Experimental: experiment results; "what actually happened"
Write an equation for a proportional relationship where the constant of proportionality (k) = 7
y=7x
A price increases from $50 to $65. What is the percent increase?
30% increase
Simplify: 4(x + 3)
4x+12
What does IQR measure?
Spread of middle 50%; Q3-Q1
Are these independent? Flipping a coin and rolling a die
Yes
A car travels 180 miles in 3 hours. What is the unit rate?
60 mph
A $80 item has 15% off and then 8% tax. Final price?
$73.44
Solve: 3x + 5 = 20
x=5
When data has outliers, should you use mean or median?
Median
Probability of drawing a spade or a diamond from a deck of cards
1/2