Which number produces a rational number when multiplied by 0.25
The Correct Answer and Explanation is:
✅ Correct Answer:
Any rational number will produce a rational number when multiplied by 0.25.
So, one correct example is: 4
📘 Explanation (300 words using the RDW strategy: Read, Draw, Write)
R – Read the Problem:
The question asks which number, when multiplied by 0.25, will give a rational number.
A rational number is any number that can be written as a fraction of two integers, like 34\frac{3}{4}, 22, or −5.5-5.5. It includes integers, fractions, and decimals that either terminate (like 0.5) or repeat (like 0.333…).
So, the question is basically asking:
What number can we multiply with 0.25 to still get a rational number?
D – Draw/Do a Strategy:
Let’s pick 0.25 and multiply it by a rational number like 4: 0.25×4=10.25 \times 4 = 1
And 1 is a rational number because it’s the integer 11\frac{1}{1}.
Also, try with a fraction: 0.25×12=0.1250.25 \times \frac{1}{2} = 0.125
0.125 is a terminating decimal — that means it’s rational.
This shows us that any rational number multiplied by 0.25 will still give a rational result.
But what if we multiply 0.25 with an irrational number, like π\pi? 0.25×π≈0.785398… (non-terminating, non-repeating)0.25 \times \pi \approx 0.785398…\text{ (non-terminating, non-repeating)}
That result is irrational, so it wouldn’t work.
W – Write an Explanation:
The number 4 produces a rational number when multiplied by 0.25, because: 0.25×4=10.25 \times 4 = 1
The result, 1, is a rational number.
In fact, 0.25 is already rational (since 0.25=140.25 = \frac{1}{4}), and multiplying two rational numbers always gives a rational result.
So, any rational number, such as 4, 1/2, -3, or 0, will work.
✅ Final Answer: 4 (or any rational number)
