Kungfu math p4 slide11 (decimals up to 3 decimal places)pdf

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Transcript of Kungfu math p4 slide11 (decimals up to 3 decimal places)pdf

• notation and place values (tenths, hundredths, thousandths)

• conversion of a decimal to a fraction

What will we learn today?

Decimals Decimals up to 3 decimal places

What is Decimal ?

Decimals

A Decimal Number

(based on the number 10)

contains a Decimal Point.

Examples:

230.01, 0.56, 1.20

Place Value

To understand decimal numbers, we must first know about Place Value.

When we write numbers,

the position (or "place") of each number is important.

Example

In the number 427:

the "7" is in the Units position, meaning just 7 (or 7 "1"s),

the "2" is in the Tens position meaning 2 tens (or twenty),

and the “4" is in the Hundreds position, meaning 4 hundreds.

In the number 427,

As we move to the left, each position is 10 times bigger!

From Units, to Tens, to Hundreds

427

In the number 427,

As we move to the right, each position is 10 times smaller.

427 From Hundreds, to Tens, to Units

If we pass the unit value,

we have to first write a decimal point

427.1 and this value is 10 times smaller than the units

Decimal Point

“four hundred twenty seven and one tenth" But,

we usually just say “four hundred twenty seven point one"

427.1

Decimal Point

The decimal point is the most important part of a Decimal Number.

It is exactly to the right of the Units position.

Without it, we would be lost ... and not know what each position meant.

With that, we can continue with smaller and smaller values, from tenths, to hundredths, and so on.

See the example below,

27.198

tenths hundredth

thousandth

units tens

decimal point

A Decimal Fraction

is a fraction where the denominator (the bottom number) is a number such as 10, 100, 1000, etc

A Decimal Fraction

is a fraction where the denominator (the bottom number) is a number such as 10, 100, 1000, etc

For example,

2.4 = 24 10

A Decimal Fraction

is a fraction where the denominator (the bottom number) is a number such as 10, 100, 1000, etc

For example,

12.4 = 124 10

A Decimal Number

can be a combination of

Whole Number and Decimal Fraction

12.4 = 12 and 4 10

Try this out!

What is the hundredths digit

in the number 356.842?

Try this out!

What is the hundredths digit

in the number 356.842?

Solution: tenths

hundredth thousandth

356.842

Try this out!

What is the hundredths digit

in the number 356.842?

Answer: 4

Are you ready to try out the questions?

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