Write the numbers in a column:
0
5
18
43
84
145
Starting with the first number 0, subtract it from
the number just below it, 5, getting 5 and write the
difference out to the right of that number in a
second column. Do that all the way down to 185-84=61
0 5
5 13
18 25
43 41
84 61
145
Do the same thing with the second column. Starting with
the first number 5, subtract it from the number just
below it, 13, getting 8, and write the difference
out to the right of that number in a third column.
Do that all the way doen to 61-41=20
0 5 8
5 13 12
18 25 16
43 41 20
84 61
145
Make one more column in the same way, and we see
that they are all 4's
0 5 8 4
5 13 12 4
18 25 16 4
43 41 20
84 61
145
Since they are all 4's we put another 4 at the
bottom of the fourth column and work backward
from right to left there by adding. That is
4+20=24, 24+61=85, 85+145=230
0 5 8 4
5 13 12 4
18 25 16 4
43 41 20 4
84 61 24
145 85
230
Answer: 230.
Edwin
