Help urgent maths

If youve drawn a sketch, you should know the height of the 4kg mass (above the ground) when the 9kg mass hits the ground. Then add on your answer from your working.

Note, Id always work to at least 3 sig fig. Youve a slight difference as youre working to 2 sig fig.

Pretty much but your initial dispalcement (height of 4 kg mass when 9 kg mass hits the ground) isnt stated. Shoiuld be clear as the 4 kg mass is 0.6 m above the ground initially and the 9 kg mass is 0.2 m above the ground. So the latter descends 0.2 m so ...

Also work to 3 sig fig at least. u is 1.228.