Question

Jessica's training on the 400 meter relay race she's trained three times this week and took 46,52 and 45 seconds on her 400m races what is the maximum amount of time she can spend on her fourth race to average At most 51 seconds​

Answer 1

The maximum amount of time she can spend on her fourth race = 61 seconds

Explanation:

Jessica's training on the 400 meter relay race.

Distance of relay = 400 m

We need to find time for fourth race so that her race to average at most 51 seconds.

Total time taken = 46 + 52 + 45 + t = 143 + t

`\texttt{Average time =}\frac{\texttt{Total time}}{4}=(143 + t)/(4)`

Average should be at most 51

That is

`(143 + t)/(4)\leq 51\\\\143 + t\leq 204\\\\t\leq61`

The maximum amount of time she can spend on her fourth race = 61 seconds

Answer 2

Explanation:

Sum of the amount of time spend on three training= 6 + 52 + 45

= 143 seconds

Average time = 51 seconds

Sum of the amount of time spend on four training's = 51 * 4 = 204

The maximum amount of time she can spend on her fourth race = 204 - 143

= 61 seconds