Facit C1-13 - Subtraction below Zero

Set up thc numLer
57. Make one forward turn.
Clcar the setting rcgisrcr. Set
up 68. Make oDe
backward turn.
The
producr
register now shows
Thc
nines
to
the left in tbe
product register show
thar rhc numbcr
89
is
negative. The register
has
co.rntcd
backwards and shows the
complemcntary
numbcr to
57 68, which is
-11
(1i+89:100).
Cleer sctting
register and set up the
rext numbcr,
3,1. Make a
forrvard turn.
Product
regirer shows
Subtroction below
Zero
Exdm?le: 57-68 +34-136
:
?
Clear sctting
register and set
up 136. Makc
one
ncgativc
turn. Product
rcgister shows
which
is a complcmcntary
number indicating
tJrat
the
lcsult is a negative
number. To rcad o{f
the
answcr, clear the setring
register and
set uP three
nines imrnediately
followed by 887
(the
number
found
behind thc nines in
the
product
register).
Turn rhc handle twice backward.
'I'he
procluct
rcgistcr
now
shows
Thc answer is
-113.
The digits to the
left of
the nouehts
arc of no importancc.
17