Math Review
Stretch Your Thinking
12. Mr. Thomas writes 4,964 on
the board. Amy says the value of
the underlined digit is 9. Chris said
the value is 900. Which student is
correct?
Explain
Stretch Your Thinking
Sara is thinking of a number. When
she rounds her number to the
nearest hundred she gets 700.
What is the greatest number Sara
can be thinking of? Explain
Stretch Your Thinking
17. How many zeros are
in the standard from of
six hundred thousand,
twenty? Explain
Stretch Your Thinking
19. When you round a
number, which digit in the
number helps you decide to
round up or round down?
Explain your answer.
Rounding Rules
• If the digit to the right of the rounding
place is 5 or more, the digit in the
rounding place increases by 1 and the
values of the places to the right of the
rounding place change to zero.
• If the digit to the right of the rounding
place is less than 5, the digit in the
rounding place does not change and the
values of the places to the right of the
rounding place change to zero.
Stretch Your Thinking
What number does this drawing
represent?
What would the number be if you took
away 200?
Stretch Your Thinking
What is the pattern?
10x3=30
100x3=300
1,000x3=3,000
What comes next?
What’s the pattern?
Stretch Your Thinking
Write
460,53
in expanded form.
Stretch Your Thinking
Write
45,039
In word form
Stretch Your Thinking
Write
300,000+3,000+10+9
In Standard Form
Stretch Your Thinking
25. A number, containing no
zeros, changed to 310,000
after it was rounded. To what
place was the number
rounded? Explain how you
know.
Stretch Your Thinking
Find the unknown value in the
number sentence:
8 x n=56
n=
Classwork: Journal page 14
• Homework: page 9
• Remembering: page 10*
*(Multiplication group replaces 1-5
of remembering; but does 6-10)