Answer:Then a few days later the activity of the sample will be due to have more of Nuclides Y than X
Step-by-step explanation:
This is because half life of nuclide X is about a day which is less than Y having half life of about a week, After a few days, we would observe that X would have disintegrated more while Y will still be predominant since it disintegrate slower than X. The time it takes for X to disintegrate will always be faster than Y.