Math
Spring Operational 2015
Grade 8
PBA Item #14
Amount of Gasoline
M20534
. Based on the unit prices, Gas Station P charges more for gasoline. The unit price for Gas Station P is $4.00 per gallon since the constant linear graph for Gas Station P shows the point (5, 20), which means it costs $20 for 5 gallons of gas. The table for Gas Station M shows that 10 gallons cost #38, so the unit price for Gas Station M is 38/10 = $3.80 per gallon. Anchor Set
A1 – A8
A1
Score Point 3 Annotations
Anchor Paper 1
Score Point 3
This response receives full credit. The response includes each of the three required
elements:

The response provides the correct unit price for both gas stations: (Gas Station P $4
dollars per gallon; Gas Station M $3.80 per gallon).

The response provides a correct determination that Gas Station P charges more for
gasoline (Gas Station P payes 20 cents more than Gas Station M because I compared
the prices . . . to find how much money you use for one gallon at each station).

The correct work for determining the unit price is provided (Gas Station P
ସ
ଵ
; Gas Station M
ଷ଼ିଵଽ
ଵ଴ିହ
=
ଵଽ
ହ
).
ସ଴ିଶ଴
ଵ଴ିହ
=
ଶ଴
ହ
or
A2
Score Point 3
Annotations
Anchor Paper 2
Score Point 3
This response receives full credit. The response includes each of the three required
elements:

The response provides the correct unit price for both gas stations: ($4 per gallon;
$3.80 per gallon). Even though the prices are not labeled, the work provided
determines that $4 per gallon is from Station P and $3.80 is from Station M.

The response provides a correct determination that Gas Station P charges more for
gasoline (gas station p charges more for each gallon of gasoline).

The correct work for determining the unit price is provided (20 ÷ 5) for Station P and
(19 ÷ 5) for Station M.
A3
Score Point 2
Annotations
Anchor Paper 3
Score Point 2
This response receives partial credit. The response includes two of the three required
elements:

The response provides the correct unit price for both gas stations: (The unit price for
the gasoline at gas station P is $4 per one gallon. The unit price at gas station M is
$3.80 per gallon).

The response provides a correct determination that Gas Station P charges more for
gasoline (station P charges more money for gasoline).
The work for determining the unit price is incorrect (work for station P: 5 ÷ 20). For this
element to receive credit, correct work or explanation for both stations must be provided.
A4
Score Point 2
Annotations
Anchor Paper 4
Score Point 2
This response receives partial credit. The response includes two of the three required
elements:

The response provides the correct unit price for both gas stations: (Gas Station P they
charge $4 per gallon; Gas Station M charges $3.80 per gallon).

The response provides a correct determination that Gas Station P charges more for
gasoline (Gas Station P charges more for gasoline per gallon).
The work for determining the unit price is incomplete (19 ÷ 5 = 3.80). The work for Gas
Station P is not provided.
A5
Score Point 1
Annotations
Anchor Paper 5
Score Point 1
This response receives partial credit. The response includes one of the three required
elements:

The response provides a correct determination that Gas Station P charges more for
gasoline (Gas Station P charges more for gasoline).
The unit price for both gas stations is missing.
The explanation for determining the unit price is incomplete. Although the explanation does
not provide the unit price, the information provided is sufficient to support which station
charges more.
A6
Score Point 1
Annotations
Anchor Paper 6
Score Point 1
This response receives partial credit. The response includes one of the three required
elements:

The response provides a correct determination that Gas Station P charges more for
gasoline (Gas Station P charges more per gallon). This determination is based on
partially correct information. The unit price for Station M is correct, and the work for
Station M is correct. The unit price for Station P is incorrect. Although the
explanation is flawed, it is sufficient for credit.
The unit price for Gas Station P is incorrect (Gas Station P charges 5$ per gallon). For this
element to receive credit, the correct unit price for both stations must be provided.
The work for determining the unit price is incomplete (19 ÷ 5 and getting 3.80). The work or
explanation for Gas Station P is not provided. The work or explanation to find the unit price
for both gas stations must be provided to receive credit.
A7
Score Point 0
Annotations
Anchor Paper 7
Score Point 0
This response receives no credit. The response includes none of the three required elements:
The unit price for both gas stations is missing.
The determination that Gas Station P charges more for gasoline is incomplete. The
determination is not based on unit price, and there is insufficient explanation to demonstrate
why Gas Station P charges more.
The work or explanation for determining the unit price is missing.
A8
Score Point 0
Annotations
Anchor Paper 8
Score Point 0
This response receives no credit. The response includes none of the three required elements:
The unit price for both gas stations is incomplete. The unit price for Station P is not provided.
The determination that Gas Station P charges more for gasoline is incorrect (They all charge
the same price of $3.80 per gallon).
The work or explanation for determining the unit price is incomplete (19 ÷ 5 = 3.8). The
work for Station P is not provided.
Practice Set
P101 - P105
P101
P102
P103
P104
P105
Practice Set
Paper
Score
P101
3
P102
0
P103
2
P104
2
P105
1