Squares and Stars and Oars

							                                         Squares and Stars

This pattern is made up of 15 congruent squares. How large are the angles at the points of the stars?
Why? Your answer to “why” should be thorough and complete. A long paragraph, which describes and
includes your math, is necessary. Pretend that you are explaining it to a fifth grader. Be thorough.
(Hint 1: Do not use a protractor to measure it.)
(Hint 2: The concept of a circle will help you figure it out.)




                                         Squares and Stars

This pattern is made up of 15 congruent squares. How large are the angles at the points of the stars?
Why? Your answer to “why” should be thorough and complete. A long paragraph, which describes and
includes your math, is necessary. Pretend that you are explaining it to a fifth grader. Be thorough.
(Hint 1: Do not use a protractor to measure it.)
(Hint 2: The concept of a circle will help you figure it out.)
                                               Oars

You have inherited a row boat with no oars. According to Shaw and Tenney, a company in Maine that
manufactures oars, the handles of the oars should overlap by 4 inches.




1. If the distance between the oarlocks, BC, is 42 inches and the overlap, AD, is 4 inches, how long
   should AB and CD be? Show your reasoning with math.
   For efficient rowing, Shaw and Tenney recommend that the inboard part of each oar (AB in each
                      7
   figure) should be     of the overall length of each oar. The paddle, EF, is 26 inches.
                      25




2. According to this information, how long should the oars of your boat be? Show all of the math to
   support your answer.
3. Oars come in lengths from 6 feet to 10 feet in 6-inch increments. What length of oar would you
   order for your boat and why?


                                               Oars

You have inherited a row boat with no oars. According to Shaw and Tenney, a company in Maine that
manufactures oars, the handles of the oars should overlap by 4 inches.




1. If the distance between the oarlocks, BC, is 42 inches and the overlap, AD, is 4 inches, how long
   should AB and CD be? Show your reasoning with math.
   For efficient rowing, Shaw and Tenney recommend that the inboard part of each oar (AB in each
                      7
   figure) should be     of the overall length of each oar. The paddle, EF, is 26 inches.
                      25




2. According to this information, how long should the oars of your boat be? Show all of the math to
   support your answer.
3. Oars come in lengths from 6 feet to 10 feet in 6-inch increments. What length of oar would you
   order for your boat and why?