Question 5
Can the product of two decimals be a natural number?
We need to see if multiplying two decimal numbers can result in a whole number.
Step 1 — What are these numbers?
Let us first understand natural numbers. Natural numbers are counting numbers. They are , and so on. They do not have any decimal part.
Now, let us understand decimal numbers. Decimal numbers have a decimal point. Examples are , , or . A number like is also a natural number. But we are looking for two decimals. Let us choose decimals that are not natural numbers.
Step 2 — Finding an example
We need to find two decimal numbers. Let us call them Decimal 1 and Decimal 2. Their product must be a natural number. Let us try Decimal 1 as . Let us try Decimal 2 as . We will multiply these two decimals. First, we can write them as fractions. is the same as . This fraction can be simplified. Next, is the same as . This fraction can also be simplified. Now, we multiply these two fractions. We multiply the numerators together. We multiply the denominators together. The product is . is a natural number. So, the product of and is a natural number.
Answer
(i) Yes.
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