7th MCA Review 4 & Proportional Relationships

The equation y = 5.6x represents a proportional relationship. What is the constant of proportionality?

(a)  

Answer explanation

y=kx is the equation for proportional relationships. k is the constant of proportionality.

Tags

CCSS.7.RP.A.2B

You wish to compare prices of trail mix online. Wal-Mart sells a 2/3 pound bag for $11.25. Target sells a ½ pound bag for $7.99. Which store cost less per pound, and what is the unit rate?

• Wal-Mart $16.88 per pound

• Wal-Mart $15.98 per pound

• Target $16.88 per pound

• Target $15.98 per pound

Answer explanation

$/pounds compare for least cost per pound.

Tags

CCSS.6.RP.A.3B

A robot can complete 8 tasks in 5/6 of an hour. How many tasks can it complete in 12 hours?

• 110.3

• 115.2

• 120.4

• 125.5

Answer explanation

Divide tasks by hours to get task per hour. Then multiply by 12 hours

Tags

CCSS.7.RP.A.1

Do x and y have a proportional relationship? If yes, what is the constant of proportionality?

• 5/2

• 2/5

• 2/3

• Not a proportional relationship

Answer explanation

All y/x must be the same.

Tags

CCSS.7.RP.A.2B

Do x and y have a proportional relationship? If yes, what is the constant of proportionality?

• 6/7

• 8/10

• 6/8

• Not a proportional relationship

Answer explanation

All y/x must be the same.

Tags

CCSS.7.RP.A.2B

A half dozen cupcakes (x) cost $15 (y). Write the equation that represents the proportional relationship of cost per cupcake.

Answer explanation

 $y\ =kx$  Fill in the  $k=\frac{y}{x}$  

Tags

CCSS.7.RP.A.2C

Three eggs (x) weigh a total of 123 grams (y).  Write the equation that represents the proportional relationship of grams per egg.

Answer explanation

 $y=kx\$  fill in  $k=\frac{y}{x}$  

Tags

CCSS.7.RP.A.2C

The graph shows the cups of flour a baker uses and the number of cookies made.What does the point (0,0) represent in this situation?

• Zero flour and Zero cookies.

• Zero flour

• Zero cookies

• Time before baking started

Answer explanation

(x,y) x axis is flour, y axis is cookies.

Tags

CCSS.HSF.LE.B.5

The graph shows the cups of flour a baker uses and the number of cookies made. What does the point (3,54) represent in this situation?

• 54 cups flour making 54 cookies

• 54 cups flour making 3 cookies

• 3 cups flour making 54 cookies

• 3 cups flour making 3 cookies

Answer explanation

(x,y) x axis is flour, y axis is cookies.

Tags

CCSS.7.RP.A.2D

What is the constant of proportionality? Note the line goes through the point (3,54).

• 5/3

• 3/5

• 3/54

• 18

Answer explanation

$k=\frac{y}{x}\ \ \left(x,y\right)$

Tags

CCSS.7.RP.A.2B