Brain Teasers
Joe and Smoe
Two friends, Joe and Smoe, were born in May, one in 1932, the other a year later. Each had an antique grandfather clock of which he was extremely proud. Both of the clocks worked fairly well considering their age, but one clock gained ten seconds per hour while the other one lost ten seconds per hour. On a day in January, the two friends set both clocks correctly at 12:00 noon. "Do you realize," asked Joe, "that the next time both of our clocks will show exactly the same time will be on your 47th birthday?" Smoe agreed. Who is older, Joe or Smoe?
Answer
To find the answer, we have to find how long it will be before the clocks show the same time again. This is when the slow clock loses six hours, and the fast one gains six hours. This will take 90 days. In 90 days they will come together at 6:00. On a calendar, there are 90 days between noon January 31, and noon May 1 in years with no leap year. If Smoe had been born in 1933, his 47th birthday would have been in 1980, a leap year. This means that Smoe must be older, born in 1932, and the time of this problem is 1979.Hide Answer Show Answer
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Comments
Very good. One of the best teasers I've reviewed. There were several different factors needed to be considered to solve this accurately. Bravo!!
Excellect job Tissue! Did you come up with this yourself? I did not take the time to try to solve it but I did follow your answer. Not sure if I ever would have figured it out.
Too complicated for me. But difficult and interesting. Nice job!
I worked at it pen and pad for about 5 minutes, then I gave up. (Thought something was missing for me to calculate, but I guess not). Tissue, now that's what I'm talking about! Good work.
I must say that no, I did not come up with this teaser.
Very Good
There are only 89 days between Jan 31 and May 1. I think it's somewhat wrong, do you think so?
I think the solution is a little wrong. We have 90 days between 31st Jan and 1st May if it is a leap year, so it must be 1980, and it will be 47th birthday for the guy who was born on 1933. So Smoe must be born on 1933 and Joe must be older.
90 days between 31 Jan and 1 May is correct in non-leap years.
31 Jan + 1 day = 1 Feb
+28 days = 1 Mar
+31 days = 1 Apr
+30 days = 1 May
30+31+28+1 = 90
Very clever teaser. I too thought that there was insufficient information to determine who was older; didn't think about leap years.
31 Jan + 1 day = 1 Feb
+28 days = 1 Mar
+31 days = 1 Apr
+30 days = 1 May
30+31+28+1 = 90
Very clever teaser. I too thought that there was insufficient information to determine who was older; didn't think about leap years.
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