Question

Ezra is training for a track race. he starts by sprinting 100 yards. he gradually increases his distance, adding 5 yards for 21 days. the explicit formula that models this situation is an=100+(n-1)5. how far does he sprint on day 21

Answer 1

the answer would be 200 i think

Answer 2

Answer:

He sprint 200 yards on day 21.

Step-by-step explanation:

The given explicit formula is:  $a_{n}= 100+(n-1)5$, where $n$ is the number of days.

For the day 21, the value of $n$ will be:  $n=21$

Plugging this $n=21$ into the above explicit formula....

$a_{21}= 100+(21-1)5\\ \\ a_{21}=100+(20)5\\ \\ a_{21}=100+100=200$

So, he sprint 200 yards on day 21.