for num 4 the answer to six is 22 the reason is this formula so write this down for n aswell
n(n+1)/2+1 the example could be as we know for 1 cut we always will have 2 slices so 1(1+1)/2+1 is 2 and for 6 cuts 6(6+1)/2+1 is 22 therefore the answer to 6 cuts is 22 and to n cuts is the formula n(n+1)/2+1