Percent Change Test Answer Key with Scoring – Grade 7

Question 1 Membership Increase (2 points)

Change: 224 − 175 = 49.

49 ÷ 175 = 0.28 = 28%.

28% increase

Scoring: 1 point for the change, 1 point for the percent.

Question 2 Price Decrease (2 points)

Change: 64 − 52.80 = 11.20.

11.20 ÷ 64 = 0.175 = 17.5%.

17.5% decrease

Scoring: 1 point for the change, 1 point for the percent.

Question 3 New and Original Prices (3 points)

(a) 250 × 1.18 = 295.

(b) 0.85 × original = 127.50, so original = 127.50 ÷ 0.85 = 150.

(a) $295; (b) $150

Scoring: 1 point for (a); in (b), 1 point for the equation and 1 point for the answer.

Question 4 Measuring a Pole (3 points)

(a) 9.6 − 9.2 = 0.4 ft.

(b) 0.4 ÷ 9.6 ≈ 0.0417 = 4.2%.

(c) 4.2% is below 5%, so yes.

0.4 ft; 4.2%; yes

Scoring: 1 point per part.

Question 5 Comparing City Growth (3 points)

(a) X: 4,200 ÷ 42,000 = 10%. Y: 1,800 ÷ 15,000 = 12%.

(b) City Y grew faster, although X added more people.

10% and 12%; City Y

Scoring: 1 point for each percent, 1 point for the comparison.

Question 6 Raise Then Cut (3 points)

(a) 40 × 1.25 = 50.

(b) 50 × 0.75 = 37.50.

(c) No. The change is 37.50 − 40 = −2.50, and 2.50 ÷ 40 = 6.25%, a 6.25% decrease.

$50; $37.50; no, 6.25% decrease overall

Scoring: 1 point per part.

Question 7 Flour Amounts (2 points)

Change: 3 34 − 2 12 = 1 14.

1 14 ÷ 2 12 = 54 × 25 = 12 = 50%.

50% increase

Scoring: 1 point for the change, 1 point for the percent.

Question 8 Museum Visitors (2 points)

Jan to Feb: 640 ÷ 3,200 = 20% increase.

Feb to Mar: −384 ÷ 3,840 = 10% decrease.

+20%; −10%

Scoring: 1 point for each percent change.