Sharon and Serene shared 18 sweets.

Sharon has 4 sweets less than Serene. This also means Serene has 4 sweets more than Sharon.

Take away 4 sweets from Serene first.
Now they each have the same number of sweets.

18 - 4 = 14

They now have the same number of sweets left. The total they have now is 14.

So, to find the number each girl has,

14 ÷ 2 = 7

Sharon has 7 sweets.




Some errors in your working :

① 18 ÷ 2 = 9, not 2 ÷ 18 = 9

② you wrote 9 - 4 = 5.

So if Sharon has 5 sweets , number of sweets Serene has
= 18 - 5 = 13

Difference = 13 - 5 = 8

If Sharon has 5 sweets, then she would have 8 less sweets than Serene, instead of the 4 sweets mentioned in the question.

The issue is, they would have 9 sweets each if the sweets were shared equally.

In order to make Sharon have 4 less
sweets than Serene (and Serene have 4 more sweets than Sharon),

You have to subtract half of that 4 instead of 4. Half of 4 is 2.

Sharon : 9 - 2 = 7
Serene : 9 + 2 = 11

Difference = 11 - 7 = 4 , which matches the information in the question

Ohh thk u so much!