Spektrum der Wissenschaft, restyled by Amanda Montañez
The hour, minute and second arms of this clock are all the identical size and transfer easily in a circle. The dial comprises hour and minute markers, however the numbers are lacking. Subsequently, it’s inconceivable to inform which one of many 12 hour markers belongs to the 12. The 2 arms on the left are positioned precisely on hour markers, and the hand on the suitable is positioned between a minute and an hour marker. What time does the clock present?
Label the decrease hand pointing left A, the upper one pointing left C and the one pointing proper B. Arms A and C are pointing precisely at hour marks. If one among these two arms is the hour hand, the minute and second arms ought to each be on high of one another and level at 12. As a result of this isn’t the case, B have to be the hour hand. As a result of the minute hand factors to a full minute, the second hand should level to 12. There are two potentialities for this. Within the first chance, A is the second hand, and C is the minute hand. Then A is on 12, and C is on 2, and it’s 10 minutes previous the hour. In that state of affairs, the hour hand should have traveled 10⁄60 = 1⁄6 of the way in which from one hour mark to the subsequent. However the image exhibits that it has already lined greater than 4⁄5 of the gap, so this chance is dominated out. Within the second chance, C is the second hand, and A is the minute hand, and it’s 10 minutes to the hour. The hour hand nonetheless has 1⁄6 of its journey from one hour mark to the subsequent, which corresponds to the picture. Consequently, the clock exhibits precisely 4:50:00.

Spektrum der Wissenschaft, restyled by Amanda Montañez
We’d love to listen to from you! E-mail us at video games@sciam.com to share your expertise.
This puzzle initially appeared in Spektrum der Wissenschaft and was reproduced with permission.