7ADMT Semester 2 Final Review

Which property is best used to calculate the material needed to cover something?

• Volume

• Lateral Area

• Total Surface Area

• Cross-Section

Answer explanation

Total Surface Area is the best property to calculate the material needed to cover an object, as it accounts for all outer surfaces, ensuring complete coverage. Other options do not provide this comprehensive measurement.

Which property is best used to calculate the material needed to fill something?

• Volume

• Lateral Area

• Total Surface Area

• Perimeter

Answer explanation

Volume is the property that measures the amount of space an object occupies, making it essential for calculating the material needed to fill a container. Lateral area and surface area relate to the outer surfaces, not the filling.

A square pyramid has a slant height of 8 cm and base edge of 10 cm. What is the lateral area?

• 320 cm²

• 160 cm²

• 80 cm²

• 100 cm²

Answer explanation

The lateral area of a square pyramid is given by the formula: Lateral Area = 1/2 * Perimeter of base * Slant height. Here, Perimeter = 4 * 10 cm = 40 cm. Thus, Lateral Area = 1/2 * 40 cm * 8 cm = 160 cm². The correct answer is 160 cm².

What is the total surface area of a rectangular prism with length 5 cm, width 3 cm, and height 4 cm?

• 94 cm²

• 60 cm²

• 52 cm²

• 100 cm²

Answer explanation

The total surface area of a rectangular prism is calculated using the formula: 2(lw + lh + wh). For this prism, it is 2(5*3 + 5*4 + 3*4) = 2(15 + 20 + 12) = 2(47) = 94 cm². Thus, the correct answer is 94 cm².

Two angles are complementary. One measures 35°. What is the other?

• 55°

• 65°

• 145°

• 75°

Answer explanation

Complementary angles add up to 90°. If one angle is 35°, the other angle is 90° - 35° = 55°. Therefore, the other angle measures 55°.

Triangle side lengths: 5 cm, 7 cm, 11 cm. Can this be a triangle?

• Yes

• No

Answer explanation

Yes, this can be a triangle. The triangle inequality theorem states that the sum of the lengths of any two sides must be greater than the length of the third side. Here, 5 + 7 > 11, so it satisfies the condition.

Two triangles have angles 30°, 60°, 90° and sides 6, 8, 10 and 3, 4, 5. Are they similar?

• Yes

• No

• Cannot determine

• Only if they’re congruent

Answer explanation

Yes, the triangles are similar because they have the same angle measures (30°, 60°, 90°). Similar triangles have proportional sides, and both sets of sides (6, 8, 10 and 3, 4, 5) maintain this ratio.

A circular mat has a radius of 4 m. What is its area?

• 50.24 m²

• 25.12 m²

• 100.48 m²

• 200.96 m²

Answer explanation

The area of a circle is calculated using the formula A = πr². For a radius of 4 m, A = π(4)² = 16π. Approximating π as 3.14, the area is about 50.24 m², making the correct answer 50.24 m².

A circle has a diameter of 10 cm. What is the circumference?

• 31.4 cm

• 62.8 cm

• 78.5 cm

• 15.7 cm

Answer explanation

The circumference of a circle is calculated using the formula C = πd, where d is the diameter. Here, d = 10 cm, so C = π × 10 ≈ 31.4 cm. Thus, the correct answer is 31.4 cm.

Which formula represents the circumference of a circle?

• A = πr²

• C = 2πr

• C = πd²

• A = 2πr

Answer explanation

The circumference of a circle is given by the formula C = 2πr, where r is the radius. This formula correctly represents the distance around the circle, making it the correct choice.