Creating Accurate Scale Drawings

This video tutorial teaches how to create and modify scale drawings using ratios and proportions. It begins with an introduction to the concept of scale drawings and proportions, followed by a detailed explanation of how to solve proportions using cross multiplication. The tutorial highlights common mistakes in setting up proportions and demonstrates how to use scale drawings to determine actual measurements. It also covers the process of creating new scale drawings from existing ones and adjusting blueprints to meet client preferences by applying scale factors.

What is the main topic of this lesson?

• How to measure distances

• How to draw blueprints

• How to make a new scale drawing using ratios and proportions

• How to build a house

What is a proportion?

• A comparison of two different units

• A method to measure distances

• A type of drawing

• An equation that relates two equal ratios

How do you solve a proportion?

• By adding the ratios

• By dividing the ratios

• By subtracting the ratios

• By cross multiplying

What are the extremes in a proportion?

• The middle numbers

• The largest and smallest numbers

• The second and third numbers

• The first and last numbers

What is a common mistake when working with proportions?

• Using decimals instead of fractions

• Not measuring correctly

• Mixing up the order of one ratio

• Using the wrong units

What must you know to use a scale drawing to determine actual measurements?

• The type of paper

• The drawing's title

• The scale being used

• The color of the drawing

If one inch stands for three actual feet, how long is a 4-inch side in actual feet?

• 12 feet

• 10 feet

• 8 feet

• 6 feet

What is the scale factor if a 30-foot side is represented by a 4-inch side?

• 3 to 1

• 4 to 1

• 2 to 1

• 5 to 2

How long should the new long side of a room be on the blueprint if the original was 8 inches and the scale factor is 5 to 4?

• 10 inches

• 8 inches

• 6 inches

• 12 inches

What is the new short side length on the blueprint if the original was 6 inches and the scale factor is 5 to 4?

• 6 inches

• 7.5 inches

• 9 inches

• 8 inches