Bluebook SAT Test Ratios, Rates, Proportional Relationships, and Units 4

Question 1

A 120-meter rope is cut into two pieces in the ratio 3:5. What is the length of the shorter piece?

Accepted Answer

45 m

Answer

Shorter piece = (3/8) × 120 = 45 meters.

Question 2

A runner finishes a 10-km race in 50 minutes. What is the runner's average speed in kilometers per hour?

Accepted Answer

12 km/h

Answer

Speed = 10 km ÷ (50/60) hr = 10 × (60/50) = 12 km/h.

Question 3

A saline solution is prepared by mixing 15 g of salt with 285 g of water. What percent of the solution by weight is salt?

Accepted Answer

5%

Answer

Total solution = 15 + 285 = 300 g; percent = (15/300) × 100 = 5%.

Question 4

If 8 identical pens cost $6.00, what is the cost, in dollars, of 20 such pens?

Accepted Answer

$15.00

Answer

Cost per pen = $6 ÷ 8 = $0.75; 20 × $0.75 = $15.00.

Question 5

A tank is filled at a rate of 6 liters per minute and drained at a rate of 4 liters per minute simultaneously. At this net rate, how many minutes will it take to accumulate 50 liters?

Accepted Answer

25

Answer

Net fill rate = 6 − 4 = 2 liters/min; time = 50 ÷ 2 = 25 minutes.

Bluebook SAT Practice Test

Bluebook SAT Practice Test

Bluebook SAT Test Ratios, Rates, Proportional Relationships, and Units 4