Solve the inequality for x: (1/8)x ? (1/2)x + 15
- A. x ? -24
- B. x ? -40
- C. x ? -40
- D. x ? -24
Correct Answer & Rationale
Correct Answer: C
To solve the inequality \((1/8)x < (1/2)x + 15\), first, subtract \((1/2)x\) from both sides, yielding \(-\frac{3}{8}x < 15\). Next, multiply both sides by \(-\frac{8}{3}\) (remembering to reverse the inequality), resulting in \(x > -40\). Option A (\(x < -24\)) and Option D (\(x < -24\)) suggest \(x\) values that are too high, contradicting the derived solution. Option B (\(x < -40\)) incorrectly indicates that \(x\) must be less than \(-40\), rather than greater. Thus, Option C accurately represents the solution \(x > -40\).
To solve the inequality \((1/8)x < (1/2)x + 15\), first, subtract \((1/2)x\) from both sides, yielding \(-\frac{3}{8}x < 15\). Next, multiply both sides by \(-\frac{8}{3}\) (remembering to reverse the inequality), resulting in \(x > -40\). Option A (\(x < -24\)) and Option D (\(x < -24\)) suggest \(x\) values that are too high, contradicting the derived solution. Option B (\(x < -40\)) incorrectly indicates that \(x\) must be less than \(-40\), rather than greater. Thus, Option C accurately represents the solution \(x > -40\).
Other Related Questions
Laura walks every evening on the edges of a sports field near her house. The field is in the shape of a rectangle 300 feet (ft) long and 200 ft wide, so 1 lap on the edges of the field is 1,000 ft. She enters through a gate at point G, located exactly halfway along the length of the field.
Laura counts the number of strides she takes during her daily walks. She takes about 80 strides to walk the width of the field from Z to W. Assuming that her stride length does not change, about how many strides does Laura take to walk all the way around the edge of the field?
- A. 267
- B. 320
- C. 450
- D. 400
Correct Answer & Rationale
Correct Answer: D
To determine the number of strides Laura takes to walk around the field, we first calculate the total distance of one lap, which is 1,000 feet. Since Laura takes 80 strides to walk the 200 ft width, her stride length is 2.5 ft (200 ft ÷ 80 strides). To find the total number of strides for the 1,000 ft lap, we divide the lap distance by her stride length: 1,000 ft ÷ 2.5 ft/stride = 400 strides. Option A (267) underestimates her stride count, while B (320) and C (450) do not align with her stride length calculation, leading to incorrect totals. Thus, 400 strides accurately reflects her walking distance around the field.
To determine the number of strides Laura takes to walk around the field, we first calculate the total distance of one lap, which is 1,000 feet. Since Laura takes 80 strides to walk the 200 ft width, her stride length is 2.5 ft (200 ft ÷ 80 strides). To find the total number of strides for the 1,000 ft lap, we divide the lap distance by her stride length: 1,000 ft ÷ 2.5 ft/stride = 400 strides. Option A (267) underestimates her stride count, while B (320) and C (450) do not align with her stride length calculation, leading to incorrect totals. Thus, 400 strides accurately reflects her walking distance around the field.
Which equation represents the graphed line?
- A. y = -1/3x +3
- B. y = 3x - 7
- C. y = 3x + 7
- D. y = 1/3x + 1
Correct Answer & Rationale
Correct Answer: D
The equation y = 1/3x + 1 accurately represents the graphed line due to its positive slope of 1/3, indicating a gradual upward rise, consistent with the line’s direction. The y-intercept of 1 shows that the line crosses the y-axis at the point (0, 1), aligning perfectly with the graph. Option A, with a slope of -1/3, suggests a downward trend, which contradicts the graph’s upward slope. Option B has a much steeper slope of 3, leading to a different angle of rise. Option C also has a slope of 3 and a y-intercept of 7, which does not match the graph’s intercept. Thus, only D accurately reflects both the slope and intercept of the line shown.
The equation y = 1/3x + 1 accurately represents the graphed line due to its positive slope of 1/3, indicating a gradual upward rise, consistent with the line’s direction. The y-intercept of 1 shows that the line crosses the y-axis at the point (0, 1), aligning perfectly with the graph. Option A, with a slope of -1/3, suggests a downward trend, which contradicts the graph’s upward slope. Option B has a much steeper slope of 3, leading to a different angle of rise. Option C also has a slope of 3 and a y-intercept of 7, which does not match the graph’s intercept. Thus, only D accurately reflects both the slope and intercept of the line shown.
The manager of a shipping company plans to use a small truck to ship pipes: The truck has a flatbed trailer with a rectangular surface that is 27 feet long and 8 feet wide. The truck will travel from Atherton to Bakersfield, where some pipes will be delivered, and then on to Castlewood to deliver the remaining pipes. The map shows the roads that connect Atherton. Bakersfield. and Castlewood.
The manager is planning to buy a new truck with better gas mileage. He collected data bout the gas mileage of one of the company's trucks. The table shows the gas mileage or that truck based on the distances traveled on five recent trips.
How many different ways can the truck travel from Atherton to Bakersfield a to Castlewood, using the roads on the map?
- A. 6
- B. 8
- C. 9
- D. 5
Correct Answer & Rationale
Correct Answer: A
To determine the number of different routes from Atherton to Bakersfield and then to Castlewood, we analyze the connections between these locations. If there are 3 distinct paths from Atherton to Bakersfield and 2 distinct paths from Bakersfield to Castlewood, the total number of combinations is found by multiplying the number of options: 3 paths (Atherton to Bakersfield) × 2 paths (Bakersfield to Castlewood) = 6 routes. Options B (8), C (9), and D (5) miscalculate the available paths or overlook the combinations of routes, leading to incorrect totals. Thus, the correct answer accurately reflects the possible travel routes.
To determine the number of different routes from Atherton to Bakersfield and then to Castlewood, we analyze the connections between these locations. If there are 3 distinct paths from Atherton to Bakersfield and 2 distinct paths from Bakersfield to Castlewood, the total number of combinations is found by multiplying the number of options: 3 paths (Atherton to Bakersfield) × 2 paths (Bakersfield to Castlewood) = 6 routes. Options B (8), C (9), and D (5) miscalculate the available paths or overlook the combinations of routes, leading to incorrect totals. Thus, the correct answer accurately reflects the possible travel routes.
The Great Pyramid at Giza in Egypt is a square pyramid that measures approximately 756 feet on each side. The height of the pyramid is approximately 450 feet. What is the approximate volume, in cubic feet, of the pyramid?
- A. 51,030,000
- B. 85,730,400
- C. 226,800
- D. 453,600
Correct Answer & Rationale
Correct Answer: B
To find the volume of a pyramid, the formula used is \( V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \). The base area of the Great Pyramid, being a square, is calculated as \( 756 \times 756 = 571,536 \) square feet. Multiplying this by the height of 450 feet gives \( 571,536 \times 450 = 257,184,000 \). Dividing by 3 yields a volume of approximately 85,728,000 cubic feet, which rounds to 85,730,400. Option A (51,030,000) underestimates the height and base area. Option C (226,800) miscalculates the base area significantly. Option D (453,600) incorrectly applies the volume formula, failing to account for the correct base area and height.
To find the volume of a pyramid, the formula used is \( V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \). The base area of the Great Pyramid, being a square, is calculated as \( 756 \times 756 = 571,536 \) square feet. Multiplying this by the height of 450 feet gives \( 571,536 \times 450 = 257,184,000 \). Dividing by 3 yields a volume of approximately 85,728,000 cubic feet, which rounds to 85,730,400. Option A (51,030,000) underestimates the height and base area. Option C (226,800) miscalculates the base area significantly. Option D (453,600) incorrectly applies the volume formula, failing to account for the correct base area and height.