Come to the front of the classroom and Pick up:

1 sheet of ¼” graph paper1 Drafting Ruler

Find ¼” scale on your drafting ruler.In the upper left corner of graph paper:Key: 1 square equals 1 sq. ft.

Draw a 12x16 rectangle.Then Draw a 4x8 to the right of it.Drawing examples are on board.

DO NOT PUT YOUR NAME IN THE UPPER RIGHT HAND CORNER

unless you wish to receive CREDIT FOR THIS ASSIGNMENT

1

• Today we are going to determine the # of plywood sheets it takes to cover our 12x16 floor.

» 1

?

How do we do that?

??

What type of shape is our 12x 16 floor?

What is the Formula for the area of a..

Rectangle?

2

• What is the formula for the area of a…

• Rectangle?

• L x W=A • Length Multiplied by Width equals Area

• L x W=A • Length Multiplied by Width equals Area

• What is area??

• ??

What about A Square?

L x W=A Length Multiplied by Width equals Area

What is another mathematical formula?

Is there another way?

• A Square?

• L x W=A • Length Multiplied by Width equals Area

• What is another mathematical formula?

• Side squared?

• When is that the best formula?

Add columns or rows?

8+8+8+8=32

4+4+4+4+4+4+4+4=32

• What about a Triangle?

• How do you find the area of a triangle?

• What is the formula for a triangle?

• What is the formula for a triangle?

• ½ the base of a triangle multiplied by the height gives you the total area?

• Area=½ bxh ?

• Area=½ bxh ?

• Can the area be found with this formula

• Area=½ hxb?

Nice work!

• But no more fun with Triangles Today!

• Back to square footage!!

Plywood comes in what size?

Four Feet by Eight feet.

4’x8’

Why 4x8?

• Standardization Baby!

• Uniformity

• Conformity

• Predictability

• Prove It!!

• Enter Mr. Tape Measure!

• 4x8=32

• Look at our sheet of plywood it is chalk lined to show square feet.

• If you count, there are 32 squares.(32 sq. ft.)

• Each square represents 12 inches by 12 “

• Review

• Formula for area is?

• Review

• Formula for area is?

• Length times Width (L X W)

• Our floor is how wide and how long?

• Review

• Formula for area is?

• Length times Width (L X W)

• Our floor is how wide and how long?

• 12 feet by 16 feet (12’ x 16’)

• 12x16

• Review• Formula for area is?• Length times Width (L X W)

• Our floor is how wide and how long?• 12 feet by 16 feet (12’ x 16’)• Therefore the formula with the answer

is…

• Review• Formula for area is?• Length times Width (L X W)

• Our floor is how wide and how long?• 12 feet by 16 feet (12’ x 16’)• Therefore the formula with the answer is…

• 12x16=192

• 12x16=192 square feet• There are _______ square feet in a sheet of plywood?

• 12x16=192 square feet

• There are _32_square feet in a sheet of plywood.

• What is a mathematical formula that will reveal how many sheets of plywood it takes to fit this floor.

• 12x16=192 square feet

• There are _32_square feet in a sheet of plywood?

• What is a mathematical formula that will reveal how many sheets of plywood it takes to fit this floor.

• Total Area / unit

• 192 / 32 = ____

• 12x16=192 square feet

• There are _32_square feet in a sheet of plywood?

• What is a mathematical formula that will reveal how many sheets of plywood it takes to fit this floor.

• 192 / 32 = 6 sheets

• Therefore if we were to optimize our efficiency, we have and even fit of (6) 4x8 plywood with no waste.

• Note the mathematical formula here.

• (6)4x8= 6x(4x8) =192

• If only it always worked out that way.

Warning!! • The home owner has

• changed their mind on the

• Size of the shed!!

• They must trim expenses!!• Allow $75.00 for cost of plywood.

Shed must utilize a exactly 5 sheets of plywood

• The customer wants to see a

• Different shape shed than a Rectangle.

• One that uses 5 pieces of plywood.

• By the end of this lesson you will have turned in:• 5 Scale Drawings on graph paper of:• 1) 12x16 floor of cabin with plywood laid out. (10pts.)• 2) 4x8 plywood (5pts)• Name and Period in upper right corner.•• Change Order• 3) 10x16 cabin floor plan showing how plywood will be laid out. (10)• 4) 12x14 floor plan for cabin with plywood laid out. (15pts.)

• 5) Show non rectangle shape that uses (5) 4x8 pieces of plywood. Plywood may be cut. (20pts)

• For each drawing: • Show mathematical formulas by each of the five drawings that

demonstrates your understanding. (see fine print)

• Bonus of up to 30 pts for neatness, detail or creativity beyond my instruction.

• For each drawing there is double points for showing formula) (150pts possible with bonus)