*don’t forget to sign in!* sketch/illustrate 2/3
Post on 19-Dec-2015
219 views
TRANSCRIPT
*Don’t forget to sign in!*
Sketch/Illustrate 2/3
Agenda:
• Exam comments• After the exam…• Making some connections
Agenda:
• Opportunity• Fraction practice
Symbols• Why do we use a X b for multiplication?• Why do we switch to a • b for
multiplication?• Why do we use c ÷ d for division?• Why do we switch to c / d or
for division? c
d
What is “cancelling”, really?
• Use cancelling to solve the following:
6000/20 =
152/8 =
345/5 =
• Using our description of cancelling above solve:
(20 + x)/20 =
What is “cancelling”, really?
• Revise our description:
152/8 = = (160 – 8)/8 =
345/5 = = (340 + 5)/5 =
And a connection
22 ÷ 7 = 3 R 1 means 22 = 73 + 1
How are these related?
5 ÷ 3 = 1 R 2 means 5 = 31 + 2
20 ÷ 12 = 1 R8 means 20 = 121 + 8
Explain why
5 ÷ 3 = (5 • 4) ÷ (3 • 4)
without doing any calculations