Like Borek: said, the translation was not perfect. Let me try to figure it out.
Concentration of With acetic acid were determined by titration. This was the litmus. This represents the change in pH = 7 (from red to blue and vice versa) does.
You performed a titration of acetic acid with a litmus indicator to determine concentration. You're stating that the color change is at pH 7. (Its not really, but that doesn't matter for this question)
The standard for measuring a concentration of 0.1 M NaOH used has been introduced to change from red to blue color is used exactly 15.3ml
So 13.5 mL of standardized 0.1 M NaOH was used to neutralize the acetic acid, as seen by the color change. Fine, we all accept that.
profits. measurement error can
The translation software fails us utterly right here. I guess you want to work in measurement error somehow. We'll work on that later.
calculate the concentration of acetic acid.
OK, now we have a question. I hope my work so far has welcomed you to our group, but I want to tell you, we don't give complete answers around here. You should first check your class notes, your textbook, or your instructor or other classmates for the correct formula you will need to use to begin to figure this out for yourself. As a hint, you've written much about litmus, and that was not necessary, many other indicators, or a pH meter, would give the same result. So maybe, by putting that out of your mind, you can begin to figure this out.