The greatest possible speed of the girl is 19m/min. and this can be determined by evaluating the HCF of 95 and 171.
Given :
A girl can walk 95m and 171m in an exact number of minutes.
The following steps can be used in order to determine the greatest possible speed:
Step 1 - According to the given data, a girl can walk 95m and 171m in an exact number of minutes.
Step 2 - Determine the HCF of 95 and 171 in order to determine the greatest possible speed of a girl.
Step 3 - The HCF of 95 and 171 is 19.
Step 4 - So, the greatest possible speed of the girl is 19m/min.
Therefore, the correct option is b).
For more information, refer to the link given below:
https://brainly.com/question/17661499
