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

He sprint 200 yards on day 21.

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.