NOCTI Applied Technical Mathematics 2

Question 1

A pipe with an outer diameter of 4 inches has a wall thickness of 0.25 inches. What is the inner diameter?

Accepted Answer

3.5 inches

Answer

The inner diameter equals the outer diameter minus twice the wall thickness: 4 - (2 x 0.25) = 4 - 0.5 = 3.5 inches.

Question 2

Convert 3/8 inch to its decimal equivalent.

Accepted Answer

0.375 inches

Answer

Divide the numerator by the denominator: 3 divided by 8 = 0.375 inches.

Question 3

What is the area of a circle with a radius of 7 inches? (Use pi approximately equal to 3.14)

Accepted Answer

153.86 square inches

Answer

Area of a circle = pi times r squared = 3.14 x 49 = 153.86 square inches.

Question 4

A staircase has a total rise of 9 feet. If each riser is 7.5 inches tall, how many risers are needed?

Accepted Answer

14

Answer

Convert 9 feet to inches: 9 x 12 = 108 inches. Then divide by riser height: 108 divided by 7.5 = 14.4, which rounds to 14 risers.

Question 5

What is 15% of 240?

Accepted Answer

36

Answer

15% of 240 = 0.15 x 240 = 36.

NOCTI - National Occupational Competency Testing Institute Practice Test