Rounding Numbers - Rang 4 Clonlara

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Transcript Rounding Numbers - Rang 4 Clonlara

Rounding Numbers …
Scoil Seanáin Naofa,
Clonlara,
Co.Clare.
A Rhyme to learn …

1, 2, 3 and 4 hey, ho, down we go

5, 6, 7 8 and 9 hey, ho up we go
Write the Answers…
Is 86 closer to 80 or 90?
90
Is 538 closer to 500 or 600?
500
Write the Answers…
Is 541 closer to 540 or 550?
540
Is 786 closer to 780 or 790?
790
Write the Answers…
Is 2, 670 closer to 2, 000 or 3, 000?
3, 000
Is 2, 670 closer to 2, 600 or 2, 700?
2, 700
Write the Answers…
Is 75 closer to 70 or 80?
It’s exactly half way which means
you round up, to the higher number
80
Is 250 closer to 200 or 300?
300
Maths Message
A newspaper reported that 20, 344
participants ran in the 2004 Dublin City
Marathon. Do you think that number is
exactly correct? Explain your answer
BrainPop: Decimals
BrainPOP | Rounding
http://www.brainpop.com/math/numbersandope
rations/rounding/
1994: 9, 059
2004: 20, 344
Do you think exactly that many people ran
in each race? Why or why not
How do you think the counts of runners
were obtained?
Rounding
numbers to a certain place value
Round 20, 344 to the nearest hundreds place
1) Mark the digit in the place you are rounding
20, 344
Rounding
numbers to a certain place value
Round 20, 344 to the nearest hundreds place
1) Mark the digit in the place you are rounding
20, 344
2) Look at the number to the right of the
underlined digit.
20, 344
If it is 5 or more, add one more
If it is 4 or less just ignore (and replace all
digits to the tight with zeros.)
Rounding
numbers to a certain place value
Round 20, 344 to the nearest hundreds place
1) Mark the digit in the place you are rounding
20, 344
2) Look at the number to the right of the underlined digit.
20, 344
If it is 0, 1, 2, 3, 4 the underline digit stays the same
If it is 5, 6, 7, 8, 9, add 1 to the underlined digit
20, 344
3) Replace all the digits to the right of the
underlined digit/place you are rounding to with
zeros
20, 300
Rounding
numbers to a certain place value
Remember our steps!! Underline, Rounding Poem,
and replace with zeros
o
o
o
Round 9, 059 to the nearest thousand
9, 059
9, 000
Round 9, 059 to the nearest hundred
9, 059
9, 100
Round 9, 059 to the nearest ten
9, 059
9, 060