Help 10
10.
She does 4 more each day than on the previous day....so.....
The number of sit-ups on the nth day can be modeled by :
17 + 4 ( n - 1)
So...on Day 12, she does
17 + 4(12 - 1) =
17 + 4*11 =
17 + 44 =
61 sit-ups