Welcome to Math with Mrs. Cross M6 A.3.1.1 and A.3.1.3 Practice place value while you wait: http://www.toonuniversity.com/flash.asp?err=496&engine=9

What we know… http://www.youtube.com/embed/3uEafe1r4GI?rel=0 - Rounding Rap

Rounding Rap Yo, this is a story all about how My math got twisted upside down, I’d like to take a minute so sit right here I’ll tell you how I got from here to there. First find the place, okay get it Arrow to the right, underline the digit, 5 or above, give it a shove-- 4 or less, stay at rest. Flex your muscles like a hero Digits to the right turn to a zero, All the other digits remain the same And that’s how its done in the rounding game! PEACE OUT!!

Estimation is ... Estimation is finding a number that is close enough to the right answer. You are not trying to get the exact right answer What you want is something that is good enough (usually in a hurry!)

When to use rounding… When the question asks you to estimate. When the question asks “about how many”…? When an exact answer isn’t possible. When an answer is difficult to obtain.

Rounding Numbers Numbers 1 – 4 = ROUND DOWN Numbers 5 – 9 = ROUND UP

Rounding Numbers Numbers 1 – 4 = ROUND DOWN Numbers 5 – 9 = ROUND UP

9 1 2 , 4 3 6 , 7 8 2, 0 5 1 Place Value ones tens billions thousands hundreds ten billions ten millions millions ten thousands hundred billions hundred millions hundred thousands

Watch me: Round to the nearest tens place: First find the place, okay get it 4 7 Circle the number in the tens place.

Round to the nearest tens place: Arrow to the right, underline the digit, 4 7 Draw an arrow to the right of the number. Underline.

Round to the nearest tens place: 5 or above, give it a shove-- 4 or less, stay at rest. 4 7

Round to the nearest tens place: 5 or above, give it a shove-- 4 or less, stay at rest. 4 7 Add 1 to the tens place.

Round to the nearest tens place: Flex your muscles like a hero Digits to the right turn to a zero, All the other digits remain the same And that’s how its done in the rounding game! 47 = _____

47 rounded to the nearest tens place is 50 The Answer 47 rounded to the nearest tens place is 50 47 50 40 Note 47 is closer to 50 on the number line.

Round to the nearest thousands place: First find the place, okay get it 3, 2 5 9 Circle the number in the thousands place.

Round to the nearest tens place: Arrow to the right, underline the digit, 3, 2 5 9 Draw an arrow to the right of the number. Underline.

Round to the nearest tens place: 5 or above, give it a shove-- 4 or less, stay at rest. 3, 2 5 9 2 shows us to do what?

Round to the nearest tens place: 5 or above, give it a shove-- 4 or less, stay at rest. 3, 2 5 9 2 should stay at rest

Round to the nearest tens place: Flex your muscles like a hero Digits to the right turn to a zero, All the other digits remain the same And that’s how its done in the rounding game! 3,259 = _______

3,259 rounded to the nearest thousands place is 3,000 The Answer 3,259 rounded to the nearest thousands place is 3,000 3,259 4,000 3,000 Note 3,259 is closer to 3,000 on the number line.

Round these numbers to the nearest ten. 1) 256 = 2) 39 = 3) 7682 = 4) 956 = 5) 1231 = 6) 344 = 260 40 7680 960 1230 340

Round these numbers to the nearest hundreds. 1) 256 = 2) 3109 = 3) 76,982 = 4) 956 = 5) 1231 = 6) 344 = 300 3100 77,000 1,000 1200

Round these numbers to the nearest thousands. 1) 1256 = 2) 32,109 = 3) 76,982 = 4) 3956 = 5) 1231 = 6) 3474 = 1000 32,000 77,000 4,000 1,000 3,000

Name the hundreds each is between 516 809 447 782 124 450 500 and 600 800 and 900 400 and 500 700 and 800 100 and 200

Name the tens each is between 84 33 58 91 23 15 80 and 90 30 and 40 50 and 60 90 and 100 20 and 30 10 and 20

Name the thousands each is between 4,309 6,500 2,833 5,432 1,875 3,598 4000 and 5000 6000 and 7000 2000 and 3000 5000 and 6000 1000 and 2000 3000 and 4000

Rounding to a Certain Place Value Estimate by rounding to the nearest ten. What numbers should you use to estimate 33 + 37? THINK: Which is the nearest ten for 33? Which is the nearest ten for 37? 30 + 40 = 70 30 31 32 33 34 35 36 37 38 39 40

Estimate by rounding to the nearest ten Estimate by rounding to the nearest ten. What numbers should use to estimate 56 + 67? A. 50+60 B. 50+70 C. 60+60 D. 60+70 D

Round each number to the nearest ten and then add. 1,357 + 729 A Round each number to the nearest ten and then add. 1,357 + 729 A. 2,000 B. 1,700 C. 2, 090 D. 2, 100 C

Round each number to the nearest ten, and then solve. 48 + 57 = 32 – 12 = 45 + 15 = 68 – 22 = 93 + 33 = 88 – 54 =

Nearest Hundred

Nearest Hundred Round each number to the nearest hundred and then add. 274 + 3,964 = A. 3,400 B. 4,100 C. 4,300 D. 4,000 C

Estimate by rounding to the nearest hundred. What numbers should you use to estimate 641 plus 378? A. 700 + 400 B. 600 + 400 C. 700 + 300 D. 600 + 300 B

Round each number to the nearest hundred, and then solve. 243 + 517 = 392 – 182 = 405 + 195 = 648 – 322 = 973 + 313 = 858 – 524 =

Which of the following should you use to estimate 5,789 – 4,678 to the nearest thousand? A. 5,000 –5,000 B. 6,000- 5,000 C. 6,000-4,000 D. 5,700-4,700 B

Round each number to the nearest thousand and then subtract Round each number to the nearest thousand and then subtract. 7,345 – 3,446 A. 4,000 B. 3,000 C. 5,000 D. 2,000 A

Round each number to the nearest thousand, and then solve. 4,218 + 1,257 = 4,832 – 1,222 = 4,985 + 1,465 = 8,642 – 2,468 = 9,093 + 6,833 = 8,478 – 1,454 =

Estimation Remember Estimation is not an exact answer It should be around the answer, but not exactly it. Round the numbers first, then calculate. Use Mental Math and Rounding to make numbers easier to work with.