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3 years ago

Which property would be useful in proving that the product of two rational numbers is ALWAYS rational?

2 answers:

8 0

C. A rational number is a number that can be expressed as the ratio of two whole numbers. The product of the rational numbers a/b and c/d are also equal to a rational number ac/bd.

Brrunno [24]3 years ago

4 0

Answer:

C) $\frac{a}{b}\times \frac{c}{d}=\frac{ac}{bd}$

Step-by-step explanation:

We have to find the property which would be useful in proving that the product of two rational numbers is always rational.

Rational number: It is that number which can be expressed as $\frac{p}{q}$ where p and q are both integers, $q\neq 0$

We know that product of two rational numbers is always a rational number.

Let $\frac{a}{b}$ and $\frac{c}{d}$ are twp rational numbers.

Product of these two rational numbers is given by

$\frac{a}{b}\times \frac{c}{d}$

$=\frac{ac}{bd}$

a, b, c and d are integers and $b\neq 0,d\neq 0$

Product of two integers is always an integer.

Therefore, ac and bd are integers and $bd\neq 0$

Hence, we can say that product of two rational numbers is always a rational number.

Option C is true.

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Answer:

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Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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Central Limit Theorem

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For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

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