Given:
Nora has a day off every 4 day while Amirah has day off every 6 days .
Nora last day off was on 29 april while Amirah was on 1 may.
To find:
When they have same day off.
Solution:
Nora last day off was on 29 april and she has a day off every 4 day.
So, her off days are
29 april, 3 may, 7 may, 11 may, 14 may, ...
Amirah last day off was on 1 may and she has day off every 6 days .
So, her off days are
1 may, 7 may, 13 may, ...
From the above two lists of off days, it is clear that they have same day off on 7 may.