Post on 04-Jan-2016
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Math Math RoundingRounding
By Grade 4By Grade 4
Use roundingUse rounding
• When the question asks you
to estimate.
When the question asks “about how many”…?
When an exact answer isn’t possible.
•To check your answer to see if you’ve made a mistake.
Memorize this PoemMemorize this Poem
Find your number.
Look right next door.
4 or less, change to 0’s.
5 or more, add 1 more.
Round the number Round the number 5 5 871 to the nearest871 to the nearest thousandthousand..
Find your number.5 871
Circle the number in thethousands place.
Round the number Round the number 5 5 871 to the nearest871 to the nearest thousandthousand..
Look right next door.
5 871
Draw an arrow to the right of the number.
Round the number Round the number 5 5 871 to the nearest871 to the nearest thousandthousand..
4 or less, change to 0’s.
5 871
8 is larger than 4 so go to the nextline of the poem.
Round the number Round the number 5 5 871 to the nearest871 to the nearest thousandthousand..
5 or more, add 1 more.5 871
Add 1 to the 5.
. . Round the number Round the number 5 5 871 to the 871 to the nearestnearest
thousandthousand..
5 or more, add 1 more.5 871
Add 1 to the 5.
+1
. . Round the number Round the number 5 5 871 to the 871 to the nearestnearest
thousandthousand..
5 or more, add 1 more.6 000
Add 1 to the 5 ( to make 6) and all the numbers
to the right of the 6 become 0’s.
+1
The AnswerThe Answer
5 871 rounded to the nearest thousand is
6 000
Round the number Round the number 22 317 to the 317 to the nearest nearest thousandthousand..
Find your number.
2 317Circle the number in the thousands
place.
Round the number Round the number 22 317 to the nearest 317 to the nearest
thousandthousand..
Look right next door.
2 317Draw an arrow to the right of the
number.
Round the number Round the number 22 317 to the nearest 317 to the nearest thousandthousand
4 or less, change to 0’s.
2 317
Since 3 is less than 4, we ignore the 2 and change the rest to 0’s.
Round the number Round the number 22 317 to the nearest 317 to the nearest thousandthousand
4 or less, just ignore.
2 0 0 0
Change the numbers to right of 2 to 0’s.
The AnswerThe Answer
2 327 rounded to the nearest thousand is
2 000
Round the number Round the number 33 5587 to the nearest 87 to the nearest hundredhundred
Find your number.
3 587Circle the number where the hundreds
are.
Round the number Round the number 33 5587 to the nearest 87 to the nearest hundredhundred
Look right next door.
3 587Draw an arrow to the right of the
circled number.
Round the number Round the number 33 5587 to the nearest 87 to the nearest hundredhundred
4 or less, change to 0’s.
3 5878 is greater than 4 so go to the next
line of the poem.
Round the number Round the number 33 5587 to the nearest 87 to the nearest
hundredhundred..
5 or more, add 1 more.
3 587Since 8 is greater than 5, add 1 to the
5.
+1
Round the number Round the number 33 5587 to the nearest 87 to the nearest hundredhundred
5 or more, add 1 more.
3 600Change the 5 to a 6 and change all the
numbers to the right to 0’s.
The AnswerThe Answer
3 587 rounded to the
nearest hundred is
3 600
Round this number to the Round this number to the nearestnearest
tenten..
Find your number.
4 875Circle the number in the tens place.
Round the number 4 8Round the number 4 8775 to the 5 to the nearest ten.nearest ten.
Look right next door.
4 875Draw an arrow to the right of the
circled number.
Round the number 4 8Round the number 4 8775 to the 5 to the nearest ten.nearest ten.
4 8755 is than greater than 4 so go to the next
line of the poem.
Round the number 4 8Round the number 4 8775 to the 5 to the nearest ten.nearest ten.
5 or more, add 1 more.
4 875Since 5 is equal to 5, add 1 to the
7.
+1
Round the number 4 8Round the number 4 8775 to the 5 to the nearest ten.nearest ten.
5 or more, add 1 more.
4 880Change the 7 to a 8 and make the rest 0’s
The AnswerThe Answer
4 875 rounded to the nearest ten is
4 880
Now try some on your own:Now try some on your own:
6 218 rounded to the nearest ten is
_ _ _ _
Now try some on your own:Now try some on your own:
6 218 rounded to the nearest ten is
6 220
Now try some on your own:Now try some on your own:
8 015 rounded to the nearest hundred is
_ _ _ _
Now try some on your own:Now try some on your own:
8 015 rounded to the nearest hundred is
8 000
Now try some on your own:Now try some on your own:
2 495 rounded to the nearest thousand is
_ _ _ _
Now try some on your own:Now try some on your own:
2 495 rounded to the nearest thousand is
2 000
Do these on paper now:Do these on paper now:Round to the nearest 1 000Round to the nearest 1 000
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
Do these on paper now:Do these on paper now:Round to the nearest 1 000Round to the nearest 1 000
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
6 000 3 000 6 000 1 000 7 000
Do these on paper now:Do these on paper now:Round to the nearest 100Round to the nearest 100
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
Do these on paper now:Do these on paper now:Round to the nearest 100Round to the nearest 100
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
5 800 3 400 6 200 1 000 6 900
Do these on paper now:Do these on paper now:Round to the nearest 10Round to the nearest 10
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
Do these on paper now:Do these on paper now:Round to the nearest 10Round to the nearest 10
1. 5 7892. 3 4113. 6 2304. 9745. 6 899
5 790 3 410 6 230 980 6 900