Deck 31: Proportions

Question 1

A gear with 35 teeth turning 100 rpm is in mesh with a gear with 7 teeth. Find the rpm of the small gear.

A) 500
B) 600
C) 700
D) 750

Answer 1

500

Question 2

$\begin{array}{|l|c|c|}\hline {\text { Item }} & \text { Quantity Needed } & \text { Cost } \\\hline 8 \text { Spark plugs } & 1 \text { set } & \$ 31.84 \\\text { Spark plug wires } & 1 \text { set } & \$ 73.92 \\\text { Distributor cap } & 1 & \$ 24.16 \\\text { Rotor } & 1 & \$ 9.10 \text { each } \\\text { Labor } & \text { Flat rate } & \$ 80.00 \\5 \% \text { sales tax on } & & \\\text { parts only } & & \\\hline\end{array}$ Use the accompanying diagram, which contains two similar triangles. If side a is 2 inches, side b is 9 inches, and side B is 18 inches, find side A in inches.

A) 3
B) 4
C) 5
D) 6

Answer 2

4

Question 3

$\begin{array}{|l|c|c|}\hline {\text { Item }} & \text { Quantity Needed } & \text { Cost } \\\hline 8 \text { Spark plugs } & 1 \text { set } & \$ 31.84 \\\text { Spark plug wires } & 1 \text { set } & \$ 73.92 \\\text { Distributor cap } & 1 & \$ 24.16 \\\text { Rotor } & 1 & \$ 9.10 \text { each } \\\text { Labor } & \text { Flat rate } & \$ 80.00 \\5 \% \text { sales tax on } & & \\\text { parts only } & & \\\hline\end{array}$ Use the accompanying diagram, which contains two similar triangles. In the larger triangle, side A is 8 feet and side C is 20 feet. In the smaller triangle, side a is 3 feet. Find, in feet, side c.

A) 7 1/2
B) 8
C) 9
D) 10

Answer 3

7 1/2

Question 4

A transmission gear ratio is 3.7:1. The crankshaft speed is 2,479 rpm. What is the rpm of the driveshaft?

A) 630
B) 635
C) 660
D) 670

Question 5

An axle ratio is 3.1:1. The driveshaft is turning 1000 rpm. What is the rpm of the rear axle to the nearest tenth?

A) 322.6
B) 322.8
C) 323.0
D) 323.2

Question 6

Proportions follow a set pattern. The units are the ____________________ on either side of the equal sign.

Question 7

The final step in solving proportions is to set the products as equal to each other, then ____________________ to solve for the unknown variable.

Question 8

A gear of 10 teeth turning 100 rpm is driving a gear of 40 teeth. Find the rpm of the driven gear.

A) 20
B) 25
C) 30
D) 40

Question 9

4:1 = 12:X. X = ____________________.

Question 10

The diameter of a driven pulley is 5 inches. The pulley is rotating at 450 rpm. The driver pulley is rotating at 1,500 rpm. Find the diameter of the driver pulley in inches.

A) 1.5
B) 2.0
C) 2.5
D) 3.0