M9 assessment 2

Which of the following situations illustrates direct variation?

• The number of workers hired increases, and the time to finish a job decreases.

• The speed of a car increases, and the time taken to travel a fixed distance decreases.

• The number of notebooks bought increases, and the total cost also increases.

• The amount of paint used decreases as the size of the wall to be painted increases.

Which of the following equations represents a direct variation between y and x?

• y = 7x

• y = 3x + 5

• y = 𝑥²

• y = 14/x

Which of the following equations represents an inverse variation between x and y?

• y = 3x

• y = x + 4

• y = 𝑥²

• y = 12/x

Which of the following equations represents a situation where y varies jointly with x and z?

• y = 5x + 2z

• y = 3xz

• y = 6𝑥/z

• y = 2𝑥² + z

Which of the following situations best illustrates an inverse variation?

• The more hours Ana works, the higher her salary becomes.

• As the speed of a vehicle increases, the time it takes to cover a fixed distance decreases.

• The number of notebooks purchased increases as the total amount paid also increases.

• The longer the rope, the higher the swing can reach.

Which of the following correctly applies the product rule in laws of exponents to simplify the expression 𝑥⁵ •𝑥^-3?

• x^-15

• x⁰

• x²

• x⁸

Which of the following shows the correct application of the “Zero Exponent Rule”?

• 7⁰ = 0

• 10⁰ = 10

• x⁰ = 1 (for x ≠ 0)

• 0⁰ = 1 (always true)

A student learns in Physics that the volume V of a gas varies directly as its temperature T and inversely as the pressure P. Suppose a gas has a volume of 240 cm3 when the temperature is 300K and the pressure is 50kPa. What will be its volume when the temperature is increased to 360K, and the pressure is raised to 60 kPa?

• 216 cm³

• 240 cm³

• 288 cm³

• 300 cm³

A printing shop charges a fixed rate of Php. 5 per page for photocopying. The total cost y is related to the number of pages x by the equation y=5x. Which of the following situations correctly applies this relationship?

• If you photocopy 20 pages, the total cost will be Php. 4.

• If you photocopy 12 pages, the total cost will be Php. 60.

• If you photocopy 10 pages, the total cost will be Php. 100.

• If you photocopy 5 pages, the total cost will be Php. 1.

The cost C of renting a tricycle is directly proportional to the number of kilometers traveled. If the cost of traveling 5 km is Php. 75, how much will it cost to travel 12 km?

• Php. 150

• Php.160

• Php.180

• Php. 200