please quietly copy onto your class notebook 9210

please quietly copy onto your class notebook 9/2/10 Our Math Goal: To apply the number theory concept of Greatest Common Factor (GCF) to solve word problems. Homework: p. 141 Try It, p. 142 #19 20 is divisible by 4, but not 3. 25 is divisible by 5, but not 4. 1) What does the word divisible mean? 2) 16 is divisible by what numbers? 3) The factors of 15 are 1, 3, 5, and 15. What are the factors of 16? 4) What do you notice about the answers to questions 2 and 3?

Real-Life problem involving GCF A. The LHS marching band has 12 members. How can the LHS marching band be divided into rows? The Baldwin marching band has 16 members. How can it be divided into rows? B. If the 12 member marching band is marching behind the Baldwin’s 16 member marching band the rows in both bands have to be the same width. What is the widest row that can be used by both bands. Draw a diagram of your result.

Group Work: This is a problem straight from the 2007 -2008 7 th grade HSA Quarter 1 assessment: 15. Ms. Nomura wants to make bags of marbles that are exactly the same for students in her class. Each bag will have marbles of three colors. She has 90 whites marbles, 30 red marbles, and 75 green marbles to make her bags. Find the greatest number of identical bags of marbles that she can make without any marbles being left over. -

Self Assessment: Two wooden planks measuring 12 and 30 feet are to be cut into the longest possible shelves of equal length so that nothing is wasted. How long will the shelves be?