Five amateur runners are competing with one another during a series of 20 designated 10 km training runs. A prize of $50 will be awarded to the runner with the overall fastest time (the fastest among all of the times in all of the runs), and a prize of $30 to the runner with the individual time that shows the greatest improvement (decrease in time) from that runner's time for the first of the designated runs. The times are shown in the table in minutes and seconds. The times for the first run are shown in boldface.| Run # | Runner A | Runner B | Runner C | Runner D | Runner E |
|---|
| 1 | ‘41:53 | ‘40:18 | ‘41:26 | ‘41:33 | ‘41:25 |
| 2 | ‘40:08 | ‘41:49 | ‘41:19 | ‘40:46 | ‘42:02 |
| 3 | ‘44:36 | ‘42:37 | ‘39:58 | ‘40:56 | ‘41:23 |
| 4 | ‘42:21 | ‘40:54 | ‘39:54 | ‘40:51 | ‘40:47 |
| 5 | ‘40:47 | ‘39:10 | ‘40:39 | ‘42:46 | ‘40:51 |
| 6 | ‘41:03 | ‘39:42 | ‘40:26 | ‘41:02 | ‘39:42 |
| 7 | ‘40:51 | ‘41:03 | ‘40:46 | ‘40:48 | ‘40:06 |
| 8 | ‘39:58 | ‘40:52 | ‘39:12 | ‘40:19 | ‘40:28 |
| 9 | ‘43:16 | ‘40:55 | ‘39:54 | ‘40:11 | ‘40:29 |
| 10 | ‘41:40 | ‘39:17 | ‘38:57 | ‘40:31 | ‘39:18 |
| 11 | ‘39:42 | ‘39:31 | ‘38:31 | ‘39:45 | ‘39:52 |
| 12 | ‘40:29 | ‘39:09 | ‘38:30 | ‘40:21 | ‘40:39 |
| 13 | ‘39:53 | ‘38:42 | ‘39:45 | ‘38:53 | ‘39:26 |
| 14 | ‘39:38 | ‘40:39 | ‘37:29 | ‘40:09 | ‘38:43 |
| 15 | ‘41:37 | ‘38:04 | ‘38:13 | ‘39:47 | ‘39:35 |
| 16 | ‘40:29 | ‘39:28 | ‘38:31 | ‘39:55 | ‘39:02 |
| 17 | ‘39:04 | ‘40:01 | ‘37:52 | ‘39:02 | ‘39:56 |
| 18 | ‘39:22 | ‘38:19 | ‘39:11 | ‘38:50 | ‘38:52 |
| 19 | ‘42:18 | ‘39:45 | ‘40:32 | ‘38:35 | ‘38:11 |
| 20 | ‘39:01 | ‘38:02 | ‘38:24 | ‘37:56 | ‘38:28 |
For each of the following statements, select Yes if the statement is accurate, based on the information provided. Otherwise, select No.Answering this question isn't particularly complicated. Basically, we just have to find a fastest time and find the biggest difference between the runners' first times and fastest times.
At the same time, getting this question correct can be a little tough because, when we sort the table, we can get the impression that we've found the value we need when actually we haven't.
So, one key move we need to make to get this question correct is to sort on each runner individually when we're looking for the runners' fastest times. If we fail to do that, we could get the impression that we're using a runner's fastest time when we're actually using another time.
Runner D will be awarded the $50 prize.This statement is fairly straightforward to handle. The $50 prize will be awarded to the runner with "
the overall fastest time (the fastest among all of the times in all of the runs)." So, we just have to find the single fastest time in the table and see whether that time belongs to Runner D.
To do so, we sort each runner's column individually from lowest to highest. Sorted, each column shows a runner's fastest time at the top since the lowest number is the runner's fastest time.
Here's what we find at the top of the runners' sorted columns:
Runner A: '39:01
Runner B: ‘38:02
Runner C: ‘37:29
Runner D: ‘37:56
Runner E: ‘38:11
We see that the lowest value of the five is Runner C's fastest time.
So, Runner C, rather than Runner D, will get the $50 prize.
Select
No.
Runner A will be awarded the $30 prize. To determine whether this statement is true, we'll compare each runner's first time with that runner's fastest time by sorting on Run # to bring up the runner's first time and then sorting on the individual runner to bring up the runner's fastest time.
Checking this statement takes a little more work, but once again, the key to getting this one right is being careful to sort the columns individually to compare each runner's first time with that runner's fastest time.
Also, we don't have to calculate exact differences between first times and fastest times. We can eliminate some runners quickly by estimating roughly and then be more exact if we have to with any that are close.
Finally, if we've read all the statements, we can see that, in checking this statement, we can also check the third statement since, to check the third statement, we have to determine which individual will get the $30 prize.
Here's what we get for the difference between the first and fastest time for each runner:
Runner A: ‘41:53 - '39:01 ≈ 42 - 39 ≈ 3
Runner B: ‘40:18 - ‘38:02 ≈ 2.25
Runner C: ‘41:26 - ‘37:29 ≈ 41.5 - 37.5 ≈ 4
Runner D: ‘41:33 - ‘37:56 ≈ 41.5 - 38 ≈ 3.5
Runner E: ‘41:25 - ‘38:11 ≈ 41.5 - 38.25 ≈ 3.25
We see the Runner C has the biggest difference, and we could have stopped checking at Runner C for this statement, but we needed to check Runner D and Runner E to check the next statement. So, if we've already read the next statement, we can get two statements done together by checking all the runners at once.
In any case, we see that Runner C rather than Runner A improved the most.
Select
No.
Both prizes will be awarded to the same individual.In checking the above two statements, we've found that Runner C had the fastest time and improved the most.
If we hadn't calculated improvements for Runner D and Runner E when we checked the previous statement, we could have done it now to confirm that Runner C improved the most.
In any case, it's true that both prizes will be awarded to the same individual, Runner C.
Select
Yes.
Answer: No,
No,
Yes