Let's break down the question bit by bit.

Dr Greg_5night shifts
Dr Steve_>5night shifts
Dr Okon_15night shifts
Dr Okon_>Dr Greg + Dr Steve
This means that the total of Dr Greg and Dr Steve is less than 15. Hence, Dr Steve cannot be 10 and above.

Dr Uche_ 8night shifts fewer than Dr Steve...

From this, it means Dr Steve has actually worked more than 8 night shifts.

But, recall we agreed that Dr Steve cannot be above 10.

So, he can't be above 10 night shifts, and he's definitely above 8 night shifts. This means that Dr Steve has worked 9 night shifts✅✅✅✅

I believe this is how it's solved. It's just a thing of concept I guess.

Let the number of night shift of Steve be S and the number of Greg be S-5(since he worked 5 night shift)
Since Ikon worked 15 more shifts than Greg and Steve combined
Ikon=S+S-5+15
=2S+10
Which is also the same as "S+5+15"
Now, let setup an equation
2S+10=S+5+15
2S+10=S+20
2S-S=20-10
S=10
Therefore, the number of night shift Steve has worked is "10*

Oga oo

Anyone who knows the answer should please post it

The question is definitely missing some information.

There is certainly some missing information in the question

Adedayo@72

I think something's missing in the question.