some rational function that I can't solve?

Question

According to this rational function

$$ f(x) = \frac{x + \frac{3}{8}}{x+ \frac{2}{5}} $$

what is $f(1/4)$?

My choices: $\frac{35}{52}$, $1$, $\frac{52}{30}$, $\frac{20}{9}$, $\frac{9}{2}$

Answer 1

top: $$\frac{2}{8}+\frac{3}{8}\ = \frac{5}{8}$$

bottom: $$\frac{5}{20}+\frac{8}{20}\ = \frac{13}{20}$$

answer: $$\frac{100}{104}$$

not sure where you're getting your options from but this is the correct answer without reducing

Answer 2

Welcome to MSE! $$f(x) = \frac{x + \frac{3}{8}}{x+ \frac{2}{5}}$$ Just put the value $x=1/4$ $$f(1/4)= \frac{\frac{1}{4}+\frac{3}{8}}{\frac{1}{4}+\frac{2}{5}}$$.

Simplify it and you will have your answer.

Answer 3

Simply multiply numerator and denominator by $40$ to get $$\frac{\frac14 + \frac{3}{8}}{\frac14+ \frac{2}{5}}=\frac{40\cdot\left(\frac14 + \frac{3}{8}\right)}{40\cdot\left(\frac14+ \frac{2}{5}\right)} =\frac{10+15}{10+16}.$$