Transcript CRCT Review

Problem
Solving
Strategies
Estimate
•
Fractions:
Estimate to 0, ½ , 1
•
Decimals: Estimate
•
+ - × ÷: Estimate
Draw a picture
prime factor tree
• fractions
• area, perimeter,
volume, surface area
•
Make a Chart
factors
 multiples
 equivalent fractions
 ratios

Guess and Check
•
Algebra

“n” – 15 = 35
a. 20 b. 50 c. 45 d. 10
Look Back
Does the answer make
sense?
Is it reasonable?
CRCT Review
Numbers and
Operations Unit
Greatest Common Factor
Find the GCF of 4 and 12
Factors of 4: 1,2,4
Factors of 12: 1,2,3,4,6,12
The GCF of 4 and 12 is 4
Least Common Multiple
Find the LCM of 3 and 12
Multiples of 3: 3,6,9,12,…
Multiples of 12: 12, 24, 36,…
The LCM of 3 and 12 is 12
Prime Factorization
Factor Tree
(Student Video)
100
25 x 4
5x 5
2 x 2 = 5x5x2x2
Fractions
Estimate.. Estimate.. Estimate..
Is the fraction closer to 0 ½ or 1?
Draw a picture if you have a doubt
Equivalent Fractions
The fractions 2/3, 4/6, and 6/9
are equivalent fractions. They
name the same basic fraction
2/3.
You can re-name fractions by
multiplying by the GIANT 1
method
Comparing Fractions
Fractions can be compared using
cross multiplication.
Which fraction is larger 5/9 or
4/5? Of course, 4/5!
5
9
4
5
Fraction Basics
Add and Subtract:
Denominators must be the same!
(Video) (Student Video)
Multiply: Top, Bottom, Simplify
(Student Video)
Divide: Just flip the second and
Multiply
(Student Video)
Decimals
Estimate… Estimate.. Estimate
When placing decimal numbers in
order, annex zeros (if needed)
Which is larger 11.19 or 11.9?
Annex zeros to give both decimals
the same number of places after
the decimal. 11.19 / 11.90.
You can see that 11.90 is the larger!
Decimals – Add / Subtract
This one is easy!
Just line up the decimals!
(Student Video)
Decimals - Multiply
Just multiply as usual. Then, count
the number of places to the right of
both decimal numbers. Move the
decimal this number of places to the
left in your answer!
What is 3.2 x 0.1?
32 x 1 = 32. Move the decimal 2
places to the left to equal 0.32
(Student Video)
Decimals - Divide
Remember, the divisor must become a
whole number before dividing!
0.5 18.45
Move the decimal in the divisor
and the dividend 1 place to
the right (Student Video)
Percent (%) of a Number
Change the % to a fraction &
multiply
or
Change the % to a decimal &
multiply.
What is 10% of 200?
1/10 x 200/1 = 20 or .10 x 200 = 20
(Student Video)
Fractions to Decimals
To change a fraction to a decimal, just
divide as usual. Annex zeros and
remember the decimal point in the
answer!
Change 3/5 to a decimal
0.6
5 3
(Student Video) (Student Video)
Percents to Fractions
Remember, percent means
“per hundred”
What is 33% as a fraction?
33/100
It’s that easy!
(Student Video)
Fractions-Decimals-Percents
1
½
1/3
¼
1/5
1/10
1.0
.50
.333
.25
.20
.10
100%
50%
33.3%
25%
20%
10%
CRCT Review
Measurement
Unit
Length
Standard Units
1 yd = 3 ft
1 ft = 12 in
1 mi= 5,280 ft
Metric Units
1km = 1000 m
1m = 100 cm
1cm = 10 mm
Metric Length
Units of Measure:
Millimeter (mm)
Centimeter (cm)
Meter (m) about 1 yard
Kilometer (km) about ½ mile
(Student Video)
Customary Volume
Customary Units
1gal = 4 qt
1gal = 8 pints
1gal = 16 cups
Metric Units
Perimeter
The distance around
any closed figure.
A border is put around a
rectangular room that is 12ft wide
and 10 ft. long. How much border
material is needed?
Answer: 44 ft.
(Student Video)
Area of Rectangular Prisms
The number of square units needed to
cover a surface enclosed by a
geometric figure.
Surface Area of a Rectangular Prism
Length x Width or Base x Height
How many 1-inch tiles are needed to
cover a square table with a side
measure of 20 inches?
Answer: 400 square inches
(Student Video)
Surface Area of Rectangular Prisms
“Panther Method” times 2
What is the total surface area of a
cereal box that measures 8in. by
2in. by 11in?
Answer: 254 square inches
(Student Video)
Volume of Rectangular Prisms
in 3D!
Length x Width x Height
What is the volume of a container
with length 10cm, width 2cm, and
height 6cm?
Answer: 10cm x 2cm x 6cm = 120 cubic cm
Circumference of Circles
∏d
or 2∏r
What is the circumference of a tire
with a diameter of 20 inches?
Answer:
Since pi = 3.14 and the diameter is 20 inches, then the circumference is 3.14 x 20
inches or 62.8 square inches!
Area of Circles
(∏r squared)
What is the area of a pizza with a
radius of 6 inches?
Answer: Since pi = 3.14 and the radius is 3cm, the area of this circle is
3.14 x 36 inches or 113.04 square cm.
CRCT Review
Geometry
Congruent Figures
2 figures are congruent when they
are the same shape and the same
size.
2in. X 4in.
2in. X 4in.
Similar Figures
2 figures are similar when they are
the same shape but not the same
size.
These triangles are similar. What
is the length of the base of
triangle 2?
1
2
6
10
4
Answer: 2
5
3
??
Geometry:Textbook Sites
Chapter 7: Proportional Relationships
7-4 Similar Figures
7-6 Scale Drawings and Maps
Chapter 8: Geometric Relationships
8-9 Congruence
8-11 Line Symmetry
Line Symmetry
A figure has line symmetry if a
single line or fold splits the shape
into congruent halves.
a regular pentagon has 5 internal
angles and 5 lines of symmetry.
Rotational Symmetry
A figure has rotational symmetry if it can be rotated and have the
figure match the original position
Order of Rotation: 5
Order of Rotation: 7
Angle of Rotation:
360° ÷ 5 = 72°
Angle of Rotation:
360° ÷ 7 = 51.4°
Geometric Nets
A flat pattern that can be folded to
make a solid figure.
Cylinder
Square Pyramid
Cube
CRCT Review
Algebra
Patterns
Fill in the missing numbers in this
table if y=6x
X
1
y
?
3
?
?
36
Holt Work Text
Ratios
A ratio compares 2 numbers.
Ratios can be written in the
following ways:
1 to 4
1:4
Holt Work Text
¼
Ratios
Cameron used 12 red beads and 60
white beads to make a necklace.
What was the ratio of red to white
beads to total beads?
a.1:5 b. 1:6 c. 1:12 d. 1:4
Answer: There are 72 total beads and 12 are red. The ratio is 12/72,
which can be simplified as 1/6 – a 1:6 ratio
Proportions
A proportion compares 2 different
ratios and shows that they are
equal.
We can determine if 8/12 = 2/3 is a
proportion by cross multiplication.
The two ratios make a proportion
when the cross products are equal.
Proportions: “Z Method”
2/8 = x/24
1/8 = 7/x
Holt Work Text
3 out of every 5 parents vote in an
election. If there are 450 parents,
how many can be expected to
vote?
Answer: 270 parents can be expected to vote
Proportions in the Form
y = kx
Jennifer earns $20 for every 2 hours
that she baby-sits. On Saturday
night, she babysat for 3 hours. How
much money does she earn?
Answer: $30
Proportions in the Form
y = kx
If you graph each equation below, all of
the graphs will be straight lines. The
steepest line would represent which
equation?
a. y=1/9x b. y=2/9x c. y=1/3x d. y=2/3x
Graphing Calculator
Evaluating Algebraic Equations
When a letter is shown beside a
number with no sign, it means to
multiply!
4a 4 x a 4·a
(Student Video)
Solving One Step Equations
if 4a = 36,
a=?
(9)
if n – 19 = 28, n = ?
(47)
if z + 10 = 12, z = ?
(2)
if x2 –1 = 24, x= ?
(5)
if 36/m = 6,
(6)
m=?
Evaluating Algebraic Equations
What is the value of this
expression when d = 3?
d2 + 14
a. 20
Answer: b
b. 23
c. 25
d. 47
CRCT Review
Data Analysis
and
Probability
Probability
…the chance than an event will
happen. Experimental probability
approaches theoretical probability
as the number of events is large.
0 : cannot occur
½ : 50-50 chance
1 : certain