Final answer:
The ratio of the minimum sound intensities heard by a 64-year-old male and a 74-year-old female is 2.5.
Step-by-step explanation:
The ratio of minimum sound intensities heard by a 64-year-old male and a 74-year-old female can be determined based on their hearing thresholds. As people age, their hearing ability may decrease. In general, the threshold for hearing sounds increases as age increases. Therefore, the 74-year-old female would have a higher hearing threshold compared to the 64-year-old male.
Let's assume the threshold for the 64-year-old male is 20 dB and the threshold for the 74-year-old female is 50 dB. To find the ratio, we divide the threshold of the 74-year-old female by the threshold of the 64-year-old male:
Ratio = Threshold of 74-year-old female / Threshold of 64-year-old male
Ratio = 50 dB / 20 dB = 2.5
So, the ratio of the minimum sound intensities heard by the 64-year-old male and the 74-year-old female is 2.5.