# Math Review.

## Presentation on theme: "Math Review."— Presentation transcript:

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 Chris is correct. The underlined digit is in the hundreds place of the number. So, it has a value of 9 hundreds, or 900.

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 749; The number 749 rounded to the nearest hundred is 700. The number 750 rounded to the nearest hundred is 800. So, 749 is the greatest number Sara could be thinking of that rounds to 700.

Stretch Your Thinking 17. How many zeros are in the standard from of six hundred thousand, twenty? Explain 600,020

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?
1,284 1,084 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? 10,00x3=30,000 The value of each place is 10 times greater.

460,53 Stretch Your Thinking Write in expanded form.
400,000+60,

Stretch Your Thinking Write 45,039 In word form 400,000+60,

Write 300,000+3,000+10+9 In Standard Form
Stretch Your Thinking Write 300,000+3, In Standard Form 303,019

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. To the ten thousands place, all of the digits to the right of the ten thousands place are zeros.

Find the unknown value in the number sentence: 8 x n=56 n=
Stretch Your Thinking Find the unknown value in the number sentence: 8 x n=56 n= N=7

Classwork: Journal page 14
Homework: page 9 Remembering: page 10* *(Multiplication group replaces 1-5 of remembering; but does 6-10)