By Jonathan Ho and Theophilus Chan

Fence of Thought

To complete your mission, follow the steps described in the different windows to solve the problem.Click the home button anytime to exit.

Click here to begin

your mission…

Situation:Bob has just bought some chickens from the market. He found a roll of fence in his barn and he wants to build the biggest area possible for his new livestock to run around. He couldn’t decide whether to fence in a square garden or a round garden with the fencing. But after doing some calculations, he found that a circular garden would give him 1380 more square meters than a square garden. So how many meters of fencing were in the roll that Bob found?Click to continue.

Which formula should we use to solve the problem?

V=l3 P=2πr

F=ma

D= f=µmg

See problem again…

Sorry, please try again.Click to go back.

Good job! Now, the second step… (click here)

Which formula shouldn’t we use to solve the problem?

A=πr2

C=2πr

A=l2

P=4d C=2πr

3

Sorry, please try again.Click to go back.

Good job! Now, the third step… (click here)

Situation:Bob has just bought some chickens from the market. He found a roll of fence in his barn and he wants to build the biggest area possible for his new livestock to run around. He couldn’t decide whether to fence in a square garden or a round garden with the fencing. But after doing some calculations, he found that a circular garden would give him 1380 more square meters than a square garden. So how many meters of fencing were in the roll that Bob found?Click to go back to question.

What is the best way to solve the problem?

See problem again…

Solve by linear equations Solve by a system of equations Solve by guess and check Solve by drawing a picture

Let’s see… The problem couldn’t be solved by a

linear equation because there are 2 unknowns.

Click to go back.

?

Let’s see… A system of equations is just the right

method to solve it!

Click to continue.?

Let’s see… Guess and check would take too long. Click to go back.

?

Let’s see… That wouldn’t be a useful method to

solve it. Click to go back.

?

Using a system of equations

These equations should be used to solve the problem because we need to find out the length of the fence.Use a calculator to help you.Click to proceed.

THE SOLUTION…After solving the equation, use the numbers here to type in your answer. Your presses will be recorded in the computer automatically.Hint: The answer has 3 digits.

THE SOLUTION…After solving the equation, use the numbers here to type in your answer. Your presses will be recorded in the computer automatically.Hint: The answer has 3 digits.

THE SOLUTION…After solving the equation, use the numbers here to type in your answer. Your presses will be recorded in the computer automatically.Hint: The answer has 3 digits.

THE SOLUTION…After solving the equation, use the numbers here to type in your answer. Your presses will be recorded in the computer automatically.Hint: The answer has 3 digits.

THE SOLUTION…After solving the equation, use the numbers here to type in your answer. Your presses will be recorded in the computer automatically.Hint: The answer has 3 digits.

AND THE SOLUTION IS…

Wrong! Click to go back, or click here to exit.

AND THE SOLUTION IS…

CORRECT!!! Thank you for helping us complete the mission.Click to end your mission,or click here to participate in a LUCKY DRAW contest!

Lucky draw… Choose a door. If the door has a prize,

you will get it. If it says “Thanks for trying”, then sorry!

Lucky draw… Choose a door. If the door has a prize,

you will get it. If it says “Thanks for trying”, then sorry!

Thanks for trying!

Lucky draw… Choose a door. If the door has a prize,

you will get it. If it says “Thanks for trying”, then sorry!

Thanks for trying!

Lucky draw… Choose a door. If the door has a prize,

you will get it. If it says “Thanks for trying”, then sorry!

You have won a pack of free food!

Come later to claim.

Lucky draw… Choose a door. If the door has a prize,

you will get it. If it says “Thanks for trying”, then sorry!

Thanks for trying!