Math Praxis (5903)
How do you find a percent change?
ex: Last week, a round-trip plane ticket from New York City to Chicago cost $118.
Today, the same ticket costs $130. What is the percent change of the ticket price
from last week to today?
set up and solve a proportion:
change %
-------- = -----
original 100
EX: To go from $118 to $130, there was a $12 increase in price, so the change is
12. The original price of the ticket is $118, so the proportion can be set up as
follows:
12 X
--- = ---- = 118X=1,200 =10.17= 10%
118 100
how to get the median
Arrange the data points from smallest to largest. If the number of data points is
odd, the median is the middle data point in the list
,A mathematics teacher determines that the median score for the most recent test
was 80 percent. Which of the following is the most accurate interpretation of the
result?
Half the students scored an 80 percent or below.
How to set a proportion
Ex: During a trip to Mexico, a traveler noticed that 10.00 US dollars were worth
191.42 pesos. Based on this exchange rate, 300.00 pesos are worth
approximately how many US dollars?
-Put all the proportions in order horizontally!!
10.00 US dollars X US dollars
----------------- = ----------
191. 42 Pesos 300.00 Pesos
3000= 191.42X
x≈15.67 US dollars
How do you solve to put the following fractions in order from least to greatest:
1/2, 3/4, 5/7, 3/16
Covert them into decimals and use power of elimination
1/2= 0.5
3/4 = 0.75
5/7 = 0.71
3/16 = 0.19
, therefore: 3/16, 1/2, 5/7, 3/4 would be least to greatest
how to find the area of a radius
A= Pi r2
how to solve:
Ellie is getting a new rug for her room. Her old rectangular rug is 5 ft by 7 ft. Her
new rug is circular with a diameter of 7 ft. How is the size of the new rug related
to the old one?
The new rug is about 3.5 ft² larger than the old one.
-Ellie's original rectangular rug has an area of 7 × 5 = 35 ft². Her new circular rug
has a diameter of 7 ft and, therefore, a radius of 3.5 ft. The area of her new rug
will be: A = π(3.5)² ≈ π(12.25) ≈ 38.5 ft². So, the new rug is about 38.5 - 35 = 3.5
square feet larger.
Simplify the expression: 4(10)^3
The 10 must be cubed first (order of operations) and then multiplied by 4.
4(10)3 = 4(1000) = 4000
what is the commutative property of addition
changing the order of two numbers being added does not change their sum
a+b=b+a
what is the commutative property of multiplication
changing the order of two numbers being multiplied does not change their
product
How do you find a percent change?
ex: Last week, a round-trip plane ticket from New York City to Chicago cost $118.
Today, the same ticket costs $130. What is the percent change of the ticket price
from last week to today?
set up and solve a proportion:
change %
-------- = -----
original 100
EX: To go from $118 to $130, there was a $12 increase in price, so the change is
12. The original price of the ticket is $118, so the proportion can be set up as
follows:
12 X
--- = ---- = 118X=1,200 =10.17= 10%
118 100
how to get the median
Arrange the data points from smallest to largest. If the number of data points is
odd, the median is the middle data point in the list
,A mathematics teacher determines that the median score for the most recent test
was 80 percent. Which of the following is the most accurate interpretation of the
result?
Half the students scored an 80 percent or below.
How to set a proportion
Ex: During a trip to Mexico, a traveler noticed that 10.00 US dollars were worth
191.42 pesos. Based on this exchange rate, 300.00 pesos are worth
approximately how many US dollars?
-Put all the proportions in order horizontally!!
10.00 US dollars X US dollars
----------------- = ----------
191. 42 Pesos 300.00 Pesos
3000= 191.42X
x≈15.67 US dollars
How do you solve to put the following fractions in order from least to greatest:
1/2, 3/4, 5/7, 3/16
Covert them into decimals and use power of elimination
1/2= 0.5
3/4 = 0.75
5/7 = 0.71
3/16 = 0.19
, therefore: 3/16, 1/2, 5/7, 3/4 would be least to greatest
how to find the area of a radius
A= Pi r2
how to solve:
Ellie is getting a new rug for her room. Her old rectangular rug is 5 ft by 7 ft. Her
new rug is circular with a diameter of 7 ft. How is the size of the new rug related
to the old one?
The new rug is about 3.5 ft² larger than the old one.
-Ellie's original rectangular rug has an area of 7 × 5 = 35 ft². Her new circular rug
has a diameter of 7 ft and, therefore, a radius of 3.5 ft. The area of her new rug
will be: A = π(3.5)² ≈ π(12.25) ≈ 38.5 ft². So, the new rug is about 38.5 - 35 = 3.5
square feet larger.
Simplify the expression: 4(10)^3
The 10 must be cubed first (order of operations) and then multiplied by 4.
4(10)3 = 4(1000) = 4000
what is the commutative property of addition
changing the order of two numbers being added does not change their sum
a+b=b+a
what is the commutative property of multiplication
changing the order of two numbers being multiplied does not change their
product
