The table shows the time taken by Jeremy to run 100 metres during his training sessions. After 3 attempts, Jeremy wanted to improve his average time taken by 1.7 seconds by running faster in the 4
th attempt. How fast should he run in the 4
th attempt in order for him to make the improvement?
Attempt |
1st |
2nd |
3rd |
4th |
Time taken (in seconds) |
18 |
18 |
24 |
? |
Total time that Jeremy took for the first 3 attempts
= 18 + 18 + 24
= 60 s
Average time that Jeremy took for the first 3 attempts
= 60 ÷ 3
= 20 s
New average time that Jeremy took for the 4 attempts
= 20 - 1.7
= 18.3 s
Total time that Jeremy took for the 4 attempts
= 4 x 18.3
= 73.2 s
Time that Jeremy should run in the 4
th attempt in order for him to make the improvement
= 73.2 - 60
= 13.2 s
Answer(s): 13.2 s