Answer:
The correct option is E. 16 min 12 sec.
Step-by-step explanation:
Consider the provided information.
When the readout indicated 24 min 18 sec, she had completed 10% of her exercise session.
That means 24 min 18 sec is 90% of her exercise time.
First convert the 24 min 18 sec into seconds:
24 min 18 sec = 1440+18 = 1458 seconds
Let x represents the 100%.



That means the total time of workout was 1620 seconds or 27 minutes.
Now she had completed 40% of her exercise session, that means the readout will indicate 60% of the time.
Calculate the 60% of 1620 as shown:

Now convert 972 seconds into minutes as shown:
972 seconds = 960 seconds + 12 seconds = 16 min 12 seconds
Hence, the correct option is E. 16 min 12 sec.