Proportional Relationships
What is the constant of proportionality in the equation y=3x?
3
4 equations:
1) y = 3x
2) x = y/3
3) x = 1/3y
4) 3 = y/x
Convert 0.08 into a fraction.
8/100 = 4/50 = 2/25
Simplify (combine like terms)
4x + 8 - 9x
-5x + 8
What is the area of a rectangle with a length of 7 cm and a width of 5 cm?
35 cm ^ 2
Perimeter is 24 cm
Sarah has 3 times as many marbles as Emily. If Sarah has 24 marbles, how many marbles does Emily have? |
8 marbles
S E
24 div 3 (x 1/3) 8
Equations: E = S/3, E = 1/3S, or S = 3E
If 4 apples cost $6, how much would 10 apples cost?
$15
What is 25% of 120?
30
Solve for x: 4x - 7 = 13
5
What is the perimeter of a triangle with sides 5 cm, 7 cm, and 10 cm?
22 cm
A car travels 70 miles per hour. How far will the car travel in 4 hours?
280 miles
Solve for x: 2/3 = x/18
x = 12
Convert 3/8 into a decimal.
0.375
What is the value of the expression (solve it)
5(3+2)
25
Find the volume of a rectangular prism with dimensions 3 cm, 5 cm, and 8 cm
120 cm ^ 3
A student scored 17 out of 20 on a test. What percentage did the student score?
17/20 = 85/100 = 85%
Is the table proportional:
x y
5 20
7 28
8 32
Yes, constant of proportionality is 4.
4 Equations:
1) y=4x
2) x = y/4
3) x = 1/4y
4) 4 = y/x
A shirt originally costs $40. If it is on sale for 30% off, what is the sale price?
$40 - $12 (30%) = $28
Solve for y:
2(y - 4) = 10
y = 9
What is the area of a triangle with a base of 3 inches and a height of 6 inches?
9 inches ^ 2
A box contains 48 chocolates. If 3/8 of the chocolates are dark chocolate, how many dark chocolates are there?
Hint: Draw a box, cut it into 8 pieces, shade in 3 pieces. If there are 48 pieces in the whole box, find how many pieces go in each section of the box.
18 dark chocolates
Is the table proportional?
x y
4 14
6 21
8 28
Yes, 14/4, 21/6, and 28/8 all equal 7/2 (3.5 or 3 1/2)
4 equations:
1) y=7/2x or y=3.5x
2) x=y/3.5 or x= y / 7/2
3) x=2/7y
4) 3.5 = y/x or 7/2 = y/x
What is 4% of 130?
100% 130
10% 13
1% 13/10, 1 3/10, 1.3
4% 5.2
Which solution below would make the equation true?
3x - 5 < 10
A. x = 8
B. x = 6
C. x = 5
D. x = 3
D. x = 3
3x - 5 < 10
3(3) - 5 < 10
9 - 5 < 10
4 < 10 - This is true
A circle has a diameter of 8 cm. What is the area?
Use 3.14 for pi.
50.24 cm ^ 2
Samantha is making a fruit salad. She uses 3/4 cup of strawberries and 5/8 cup of blueberries. How much fruit did she use in total? Express your answer as a mixed number.
3/4 cup of sb + 5/8 cup of bb
6/8 cup of sb + 5/8 cup of bb = 11/8 cups of fruit
11/8 = 1 3/8 cups of fruit