Other Proportion Problems Slideshow 32, Mathematics Mr Richard Sasaki Room 307

OBJECTIVES UNDERSTAND HOW K AFFECTS Y = KX BEING ABLE TO CALCULATE MIXED WORDED PROPORTIONAL VALUES UNDERSTAND HOW LENGTHS AND AREAS RELATE TO ONE ANOTHER

DIRECT PROPORTION Hopefully after completing your project you found out that k causes the following effect…

NOTATION Recently, some new notation is being used so I want to make sure that you all understand what it means.

MIXED PROPORTION QUESTIONS We’ve learned all we need to for 7 th grade proportion now. We just need to be able to identify what kind of question is being asked in a particular context. This type of question can be very challenging. You can only answer it when you know exactly what it means. Understanding the meaning is the challenging part.

EXAMPLE What kind of proportion is this referring to? Direct Proportion What do the two variables represent?

Direct Proportion She is drinking at the same rate. Direct Proportion # of CDs left (this means the number of CDs sold)

ONE LAST THING TO THINK ABOUT… If it takes one man an hour to unload bricks from a van, how long would it take five men? (Let’s forget assumptions for a minute.) More men to help will make things quicker, not slower so be careful! We would do 1 divided by 5 = 12 minutes.

PROPORTION IN SHAPE Let’s move onto something a bit easier! A cm 2 X cm Y cm If the area A remains constant, what is the relationship between X and Y?

Direct Proportion Inverse Proportion Direct Proportion k = 1 (they are the same) k = 4 Directly proportional 21cm Directly proportional