Which number produces a rational number when added to [tex]\frac{1}{5}[/tex]?

A. [tex]-1.41421356 \ldots[/tex]

B. [tex]-\frac{2}{3}[/tex]

C. [tex]\pi[/tex]

D. [tex]\sqrt{11}[/tex]



Answer :

To determine which number produces a rational number when added to [tex]\(\frac{1}{5}\)[/tex], consider the following step-by-step solution:

1. Identify the given number:
The given number is [tex]\(\frac{1}{5}\)[/tex], which is a rational number.

2. Evaluate the options provided:

A. [tex]\(-1.41421356 \ldots\)[/tex] is an approximation of [tex]\(-\sqrt{2}\)[/tex], which is an irrational number. Adding an irrational number to [tex]\(\frac{1}{5}\)[/tex] will yield an irrational number.

B. [tex]\(-\frac{2}{3}\)[/tex] is a rational number. Adding two rational numbers will always result in a rational number. Let's perform the addition:
[tex]\[ \frac{1}{5} + \left(-\frac{2}{3}\right) = \frac{1}{5} - \frac{2}{3} \][/tex]
To add these fractions, find a common denominator, which is 15:
[tex]\[ \frac{1}{5} = \frac{3}{15}, \quad \frac{2}{3} = \frac{10}{15} \][/tex]
Thus,
[tex]\[ \frac{3}{15} - \frac{10}{15} = \frac{3 - 10}{15} = \frac{-7}{15} \][/tex]
The result, [tex]\(\frac{-7}{15}\)[/tex], is a rational number.

C. [tex]\(\pi\)[/tex] is an irrational number. Adding an irrational number to [tex]\(\frac{1}{5}\)[/tex] will yield an irrational number.

D. [tex]\(\sqrt{11}\)[/tex] is an irrational number. Adding an irrational number to [tex]\(\frac{1}{5}\)[/tex] will yield an irrational number.

3. Conclusion:
The only option that produces a rational number when added to [tex]\(\frac{1}{5}\)[/tex] is:
[tex]\[ \boxed{B. -\frac{2}{3}} \][/tex]