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4. DECIMALS

Rounding Off 

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Rounding Off Decimals

Decimals can be rounded off to a givennumber of decimal places.

Whole Number 

 1 decimal place

 2 decimal places

 3 decimal places

Round off a decimal

nearest to,

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Rounding Off Decimals Nearest to Whole Number 

Eample 1! 3.3

"o round 3.3 to #hole number, #e loo$ atthe first digit after decimal point.

3.3

"he first digit after decimal point is 3. 3 is less than %,so #e round b& do#n discarding the decimal and the

digit to the right of the decimal point.

3.3 is nearer to 3 than 4, so 3.3 ≈ 3

3.3

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Rounding Off Decimals Nearest to Whole Number 

Eample 2! %.'"o round %.' to #hole number, #e loo$ at the first digit

after decimal point.

%.'

"he first digit after decimal point is '. ' is greater than %, so#e round up the decimal b& adding 1 to % and discarding the

decimal point and all digits to the right of the decimal point.

5.8 is nearer to 6 than 5, so 5.8 ≈ 6

%.'(1

)

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Rounding Off Decimals Nearest to 1 Decimal *lace

Eample 1! +.32+"o round +.32+ to 1 decimal place, #e loo$ at the second 

digit after decimal point.

+.32+

"he second digit after decimal point is 2. 2 isless than %, so #e round do#n the decimal b&

discarding all the decimal places after number 2.

So, 9.329 ≈ 9.3 ( 1 decimal place )

+.3

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Rounding Off Decimals Nearest to 1 Decimal *lace

Eample 2! ).-)"o round ).-) to 1 decimal place, #e loo$ at the second 

digit after decimal point.

).-)

"he second digit after decimal point is -. - is greater

than %, so #e round up the decimal b& adding 1 to

number and discarding all the decimal places after

number -.

So, 6.476 ≈ 6.5 ( 1 decimal place )

+.-)(1

+.%-)

+.%

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Rounding Off Decimals Nearest to 2 Decimal *laces

Eample 1! 23.%-"o round 23.%- to 2 decimal places, #e loo$ at the third 

digit after decimal point.

23.%-

"he third digit after decimal point is . is

less than %, so #e round do#n the b&

discarding the decimal place after number -.

So, 23.574 ≈ 23.57( 2 decimal places )

23.%- 23.%-

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1%.'+

Rounding Off Decimals Nearest to 2 Decimal *laces

Eample 2! 1%.''+

1%.''+

"he third digit after decimal point is +. + is

greater than %, so #e round up the decimal b&

adding 1 to ' and discarding the decimal point

and all digits to the right of the decimal point.

So, 15.889 ≈ 15.89 ( 2 decimal places)

1%.''+(1

"o round 1%.''+ to 2 decimal places, #e loo$ at the third 

digit after decimal point.

1%.'+)

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2.1+'

Rounding Off Decimals Nearest to 3 Decimal *laces

Eample 1! 2.1+'3"o round 2.1+'3 to 3 decimal places, #e loo$ at the fourth 

digit after decimal point.

2.1+'3

"he fourth digit after decimal point is 3. 3 is less

than %, so #e round do#n b& discarding the

decimal place after number '.

So, 2.1983 ≈ 2.198( 3 decimal places )

2.1+'3

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-.12

Rounding Off Decimals Nearest to 3 Decimal *laces

Eample 2! -.123+

-.123+

"he fourth digit after decimal point is +. + is

greater than %, so #e round up the decimal b&

adding 1 to 3 and discarding the decimal point and

all digits to the right of the decimal point.

So, 7.1239 ≈ 7.124 (3 decimal places)

-.123+(1

"o round -.123+ to 3 decimal places, #e loo$ at the fourth 

digit after decimal point.

-.12+

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EER/0E 1EER/0E 1

Round off 3.+') to,

a Whole number 

b 1 decimal place

c 2 decimal places

d 3 decimal places

3%

3%.

3.+'

3.+'%

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EER/0E 2EER/0E 2

Write +.-%3 correct to ,a Nearest #hole number 

b 1 decimal place

c 2 decimal places

d 3 decimal places

1

+.-

+.-1

+.-%

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