Another Peek Beyond the Point | IT

Question 6

Can the product of a decimal and a natural number be a natural number?

Solution

We check if a decimal and natural number product can be natural.

Step 1 — Defining our numbers

Let us understand natural numbers.

Natural numbers are counting numbers.

Examples are 1, 2, 3, 4, and so on.

Let us understand decimal numbers.

Decimal numbers have a whole part.

They also have a fractional part.

They are written with a decimal point.

Examples are 0.5, 2.75, 10.0.

A natural number can be a decimal.

For example, 5 is the same as 5.0.

Step 2 — Finding a product

Let us pick a decimal number.

We choose 0.5.

Let us pick a natural number.

We choose 2.

Now, let us find their product.

We multiply the decimal by the natural number.

$0.5 \times 2$

$= 1.0$

The result is 1.0.

1.0 is the same as 1.

$\boxed{1 \text{ (a natural number)}}$

Step 3 — Another example

Let us try another example.

We choose the decimal 1.2.

We choose the natural number 5.

Let us find their product.

$1.2 \times 5$

$= 6.0$

The result is 6.0.

6.0 is the same as 6.

$\boxed{6 \text{ (a natural number)}}$

Answer

Yes, the product of a decimal and a natural number can be a natural number.

More questions in IT

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Write the following fractions as a sum of fractions and also as decimals:

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Suppose we know that 596 × 248 = 147808, can you immediately write down the product of 5.96 × 24.8?

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Q. By looking at the above examples, can you frame a rule to multiply two decimals?

Q10

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Q12

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Q13

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Q14

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Q15

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Q16

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Q17

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Q18

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Q19

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Q20

How many years are divisible by 4 in 100 years?

Q21

Can you form different expressions for the same question?

Q22

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Q. Can you write an expression for the number of days in 100 calendar years with this new adjustment?

Q23

With this final scheme of leap years can you calculate the number of calendar days in 10,000 years and the number of actual days the Earth will take to make 10,000 revolutions around the Sun? What is the difference? If there is a big difference, can you suggest a way to fix this problem?

Q24

Do you wonder how people figured out that the Earth completes one revolution around the Sun in exactly 364.2422 days?