How many times greater is the half-life of 24Na (15 hours) to that of 216Po (0.15 seconds)

Half-time of 24 Na (15hrs) would be 54000 seconds while 216Po would be 0.15s. Because it says how many times *greater*, I opt to divide 54000 seconds by 0.15 seconds which would equal 360000. The answer is 4.4*10^10 (44000000000). I can't seem to get this.. could some please tell me what I did wrong? Thanks.

2 answers

15hr* 3600s/hr = 54000s

54000/0.15 = 360,000

you are correct. Something's messed up here.
Alright, thank you Steve. If it really is the case that the answers were wrong, I will hate myself so much for spending more than half an hour trying to figure what's wrong, more so, posting the question on the Internet...