14. The doctor donates 6.4 % of her salary to various charities. What fraction of her salary is this?
Answer: A
The fraction of the doctor's salary that she donates to charities is 8/125.
The doctor donates 6.4% of her salary, which can be expressed as the fraction 8/125. This conversion is achieved by recognizing that 6.4% is equivalent to 6.4/100, which simplifies to 8/125 when both the numerator and denominator are multiplied by 25.
A) 8 / 125
This option is correct because 6.4% can be converted to a fraction by writing it as 6.4/100. By multiplying the numerator and denominator by 25, we obtain 8/125, accurately reflecting the portion of her salary that is donated.
B) 16 / 25
This option is incorrect as it represents a fraction that amounts to 64%, not 6.4%. The fraction 16/25 simplifies to 64/100, which is significantly greater than the actual percentage donated.
C) 8 / 115
This option is also incorrect because the fraction 8/115 does not equate to 6.4%. When calculated, 8/115 is approximately 6.96%, which exceeds the percentage of the doctor's donation.
D) 4 / 625
This option is incorrect as well. The fraction 4/625 is approximately 0.0064 or 0.64%, which is far less than the 6.4% donated by the doctor. This fraction does not represent the intended donation amount.
Conclusion
The correct answer, 8/125, accurately represents the fraction of the doctor's salary that she donates to charities, corresponding to 6.4%. The other options fail to match this percentage, either being too high or too low, thus confirming that 8/125 is the only valid choice.