Ratios, Rates, and Proportions Flashcards
6 cards from real Rise Placement Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Ratios, Rates, and Proportions flashcards as text
A recipe for a fruit smoothie requires 6 ounces of yogurt and 15 ounces of mixed berries. To maintain the same taste, what is the ratio of yogurt to mixed berries in its simplest form?
Answer: 2:5
To simplify the ratio 6:15, find the greatest common divisor (GCD) of both numbers. The GCD of 6 and 15 is 3. Divide both parts of the ratio by 3: 6 ÷ 3 = 2 and 15 ÷ 3 = 5. The simplest form of the ratio is 2:5.
A car travels 120 miles on 5 gallons of gasoline. Which of the following proportions could be used to determine how many miles (x) the car can travel on a full tank of 13 gallons?
Answer: 120/5 = x/13
A proportion sets two ratios equal to each other. The ratio of miles to gallons must be consistent on both sides of the equation. The initial rate is 120 miles to 5 gallons (120/5). The new situation compares an unknown number of miles (x) to 13 gallons (x/13). Setting these equal gives the correct proportion: 120/5 = x/13. [9, 25]
A customer is comparing two bulk-bin options for almonds. Store A sells almonds for $11.88 for 18 ounces. Store B sells almonds for $8.04 for 12 ounces. Which store offers the better price per ounce?
Answer: Store A
To find the unit price, divide the total cost by the number of ounces. For Store A: $11.88 ÷ 18 ounces = $0.66 per ounce. For Store B: $8.04 ÷ 12 ounces = $0.67 per ounce. Comparing the unit prices, Store A is cheaper. [15, 34]
The scale on a blueprint for a new park is 1 inch : 4 feet. If a rectangular playground on the blueprint measures 8.5 inches by 12 inches, what is the actual area of the playground in square feet?
Answer: 1632 sq ft
First, convert the blueprint dimensions to actual dimensions. Length: 12 inches * 4 feet/inch = 48 feet. Width: 8.5 inches * 4 feet/inch = 34 feet. Next, calculate the area using the actual dimensions: Area = Length × Width = 48 feet × 34 feet = 1632 square feet. [12, 17]
A cyclist completes a 63-kilometer route in 2.25 hours. What was the cyclist's average speed in kilometers per hour (km/h)?
Answer: 28 km/h
Average speed is a rate calculated by dividing the total distance traveled by the total time taken. Speed = Distance / Time. In this case, Speed = 63 kilometers / 2.25 hours = 28 kilometers per hour. [1, 2]
In a community choir, the ratio of altos to sopranos is 3:5. If there are 25 sopranos, how many total members are in the choir between these two sections?
Answer: 40
The ratio 3:5 means for every 5 sopranos, there are 3 altos. Since there are 25 sopranos, we can find the value of one 'part' of the ratio: 25 sopranos / 5 parts = 5 members per part. To find the number of altos, multiply their parts by this value: 3 parts * 5 = 15 altos. The total number of members is the sum of altos and sopranos: 15 + 25 = 40. [21, 35]