Relative Frequencies Worksheets Grade 8

1. (2.4 × 10^8) ÷ (6 × 10^3) = ?
2. A coordinate plane shows triangle ABC with vertices at A(1, 2), B(4, 5), and C(7, 2). Triangle A'B'C' is created by applying the transformation (x, y) → (2x, 3y) to all vertices of triangle ABC. What is the ratio of the area of triangle A'B'C' to the area of triangle ABC?
3. A wildlife biologist is tracking the population growth of two different species of birds in a nature reserve. Species A started with 120 birds and increases by 15 birds each month. Species B started with 80 birds and increases by 20 birds each month. After how many months will both bird populations be equal?

…and 4 more problems

1. Emma surveyed 175 students about whether they prefer reading fiction or non-fiction. The results are shown in the two-way table below. Calculate the relative frequency of preferring fiction among students who are in Grade 8. Then determine if there is an association between grade level and preference for fiction. | | Fiction | Non-Fiction | Total | |------------|---------|-------------|-------| | Grade 7 | 45 | 35 | 80 | | Grade 8 | 55 | 40 | 95 | | Total | 100 | 75 | 175 | What is the relative frequency of preferring fiction among Grade 8 students? Does this suggest an association between grade level and preference for fiction?
2. A cylindrical water tank has a diameter of 12 feet and a height of 20 feet. The tank is filled to 80% of its capacity. What is the volume of water in the tank, in cubic feet? (Use π = 3.14)
3. A survey of 300 students asked about their preferred sport (Basketball or Soccer) and whether they prefer morning or afternoon practice. The two-way table shows: Basketball-Morning: 45, Basketball-Afternoon: 75, Soccer-Morning: 60, Soccer-Afternoon: 120. Calculate the relative frequency of students who prefer morning practice given they prefer Basketball. Do the relative frequencies suggest an association between sport preference and practice time preference?

…and 1 more problems

1. Kaia surveyed 150 students at her school about whether they walk to school or are driven. The results are shown in the two-way frequency table below. | | Walk to School | Driven to School | Total | |----------------|----------------|------------------|-------| | 6th Grade | 18 | 42 | 60 | | 7th Grade | 28 | 12 | 40 | | 8th Grade | 30 | 20 | 50 | | Total | 76 | 74 | 150 | Based on the relative frequencies, is there an association between grade level and how students get to school? Explain your reasoning by comparing the relative frequencies of walking to school for each grade level.
2. A research team is studying the relationship between daily screen time and hours of sleep among middle school students. They surveyed 120 students and created this two-way relative frequency table: | Screen Time / Sleep | Less than 8 hours | 8 or more hours | Total | |---------------------|-------------------|-----------------|-------| | Less than 2 hours | 0.15 | 0.25 | 0.40 | | 2-4 hours | 0.20 | 0.20 | 0.40 | | More than 4 hours | 0.15 | 0.05 | 0.20 | | Total | 0.50 | 0.50 | 1.00 | Based on the relative frequencies, what association exists between daily screen time and hours of sleep? Explain your reasoning using the data.
3. Mere, a school environmental officer, surveyed 240 students to investigate whether there is an association between grade level (Grade 7 or Grade 8) and whether they regularly recycle. The results are shown in the two-way frequency table below: | | Recycles | Does Not Recycle | Total | |---------------|----------|------------------|-------| | Grade 7 | 72 | 48 | 120 | | Grade 8 | 60 | 60 | 120 | | Total | 132 | 108 | 240 | Calculate the relative frequencies (as percentages) of students who recycle for each grade level. Based on these relative frequencies, is there an association between grade level and recycling behavior? Explain your reasoning.

…and 2 more problems