Take, for example, four consecutive negative numbers, say

${\displaystyle {}^{-}7{,}^{-}6{,}^{-}5{,}^{-}4}$

Now place + and / or - signs between them.

e.g.

${\displaystyle {}^{-}7{+}^{-}6{+}^{-}5{+}^{-}4}$

${\displaystyle {}^{-}7{-}^{-}6{+}^{-}5{-}^{-}4}$

There are other possibilities. Try to list all of them.

Now work out the solutions to the various calculations.

e.g.

${\displaystyle {}^{-}7{+}^{-}6{+}^{-}5{+}^{-}4{=}^{-}22}$

${\displaystyle {}^{-}7{-}^{-}6{+}^{-}5{-}^{-}4{=}^{-}2}$

Choose a different set of four consecutive negative numbers and repeat the process.

Take a look at both sets of solutions. Notice anything?
Can you explain any similarities?

Can you predict some of the solutions you will get when you start with a different set of four consecutive negative numbers?
Test out any conjectures you may have.

Try to explain and justify your findings.