8/29 7th Grade Period 5

Date: 8/29
Essential Question: What is the distance between a number and zero?
Opening: Discuss Behavior Goals
Work Session: Helicopters and Submarines Day 3
Closing:Ticket Out The Door
Vocabulary: negative numbers, positive numbers, integers, number line, absolute value
Standard: Understand p + q as the number located a distance |q| from p.
1. 81+-123
2. -5+-9+13
3. -13-(-12) +15

 

Helicopters and Submarines

You are an engineer in charge of testing new equipment that can detect underwater submarines from the air.

Part 1: The first three hours

During this part of the test, you are in a helicopter 250 feet above the surface of the ocean. The helicopter moves horizontally to remain directly above a submarine. The submarine begins the test positioned at 275 feet below sea level.

          

􀂃 After one hour, the submarine is 325 feet below sea level.

          

􀂃 After two hours, the submarine dives another 23 feet.

􀂃 After three hours, the submarine dives again, descending by an amount equal to the average of the first two dives. (hour 1 depth + hour 2 depth then ÷ by 2)

Part 2: The next three hours

The equipment in the helicopter is able to detect the submarine within a total distance of 575 feet.

          

􀂃 At the end of the fourth hour, the helicopter dives to 125 feet and the     submarine rises to 275 feet.

          

􀂃 At the end of the fifth hour, the submarine returns to the same depth that it was  

       at the beginning of the test and the helicopter rises to 275 feet.

          

􀂃 At the end of the sixth hour, the submarine descends to 1.5 times its second

       hour position.