For 5., it number machine is -4. You would then subtract 4 from 3 giving you a negative number. 3-4=-1, -1-4=-5, and -5-4=-9. The answer for 5. would then be -1, -5, -9.
For 6., it looks like you are dividing by two each time. 6 divided by 2 is 3. 3 divided by 2 is 1.5, and 1.5 divided by 2 is.75. so the answer is 3,1.5,.75.
Hope this helps!