Keenan currently does a total of 8 pushups each day. He plans to increase the number of pushups he does each day by 2 pushups until he is doing a total of 30 pushups each day.

8 + 2x = 30

Step-by-step explanation:

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12

Step-by-step explanation:

Given that

Current count of pushups = 8

Number of increase in pushups each day = 2

The desired pushup goal on daily basis = 30

Days require = x=?

as we can conclude the number of pushups would increase by following sequence

8, 10, 12, 14, 16, ... 30

Now as we can be the number of pushups by a constant number each day it means this sequence is arithmetic.

First term of our sequence is X1 and the final term is Xn, and the difference between two consecutive terms (Common Difference) is 2.

So

X1 = 8

Xn = 30

d = 2

Using the formula of nth term for arithmetic sequence

Xn = X1 + (n-1) d

Substituting the values

30 = 8 + (n-1) 2

30-8 = (n-1) 2

22 = 2n - 2

22+2 = 2n

2n = 24

n = 24/2

n = 12

So, it means on the 12th day he will have to do 30 pushups if he starts from 8 and increase 2 pushups each day.