It is 1595. Put it on excel so you can better have an overview how it is done. You need 5 columns, column A-E. On column A, put 1 to 5 in rows 1 to 5. On column C, put the answers: 2, 7, 26, 101 and 400. On column D, put number 3 in all 5 rows. Back on column B, insert =sum(C1-A1) on row 1 and copy till row 5. On column E, insert =sum(B1+C1*D1) on row 1 and copy till row 5 and you will get 1595 at the end.
Looking from left to right it is increasing
So you are rounding 60.89.
I don't know which way you are aiming for to round, but here are some possible answers.
61.00
60.90
61.90
now, the one below that, which is equivalent to that? well, just look above it
