Here’s some added interesting info regarding this week’s BGTN #2. Try this trick on somebody. Ask him or her to scratch their scalp with a fingernail and then ask them if they can hear it. The answer is yup, they can unless their keratin has been replaced with some graphene aerogel. The reason is sound conduction through bones. Now ask a bystander or sitter or whatever if they can hear it too. The answer is nope they can’t unless the scalp scratcher is using the business end of a claw hammer to cleave his or her cranium in two. The reason is sound conduction through air. That still doesn’t solve the problem though.
So if we can’t hear our own heartbeats all the time (to the point that docs have to use stethoscopes to hear that dickey ticker) how come we instantly know when we’ve missed a beat or two -- like as when that babe or hunk suddenly makes our knees the consistency of jelly pudding?
THROUGHPUT
(The peat-barrel aged one was about a country where in case of a hung jury you’re blindfolded and given two urns containing 25 white balls and 25 black balls. You have to choose a ball at random where black = death; white = undeath, However, they also offer the option of distributing the balls in any which way you like before the blindfolding. How to maximise your chances of not meeting the two horned tailed guy who lives downstairs?)
Put one white ball in the first urn and the remaining 99 in the second. If you choose the first urn, you go free. If you choose the second, you have 49 chances out of 99, or nearly 50 percent. Altogether this strategy raises your chance of survival to nearly 75 percent. -- Dhruv Narayan, dhruv510@gmail.com
Leaving things in the original condition (the first urn with 25 white balls, the second urn with 25 black balls), the chances of escape is 1:2. But, if you transfer 24 white balls to the second urn, the chances of escape increases. If you choose the first urn containing one white ball, you are free. Even if the second urn is chosen still the chances of picking up a white ball is 24:49. This is the maximum chance of escape. -- Dr P Gnanaseharan, gnanam.chithrabanu@gmail.com
A crooked member of the jury may replace the single white ball in the urn with a black ball (and put the white in the other urn w/o your knowledge since you’ll be blind-folded) and your chance of getting a death penalty climbs to 74.49%. -- Ajit Athle, ajitathle@gmail.com
(The second problem was about you hoping to run 26.5 miles while averaging less than 9 minutes per
mile. But friends who measure your time along various mile-long segments anywhere, measure exactly 9 minutes. Yet your average is still less than 9 minutes per mile. Possible?)
You must have run every alternate half mile from start slower than the preceding half mile. Say the first half mile in 4 minutes, next half mile in 5 minutes and so on alternating till 26.5 miles. Now average speed of total is less than 9 minutes because last half mile is in faster time 4 minutes. But when any 1 mile segment will be in 9 minutes because it contains half mile segments run in 4 and 5 minutes. -- Raghavendra Rao Hebbani, rao.raghavendrah@gmail.com
I run the first half-mile in 4 minutes and the next in 5 minutes, and continue alternating like this throughout the marathon. This way I’ll cover any measured mile in 9 minutes. But because the “fast” segments outnumber the “slow” ones, my average pace for the whole run is less than 9 minutes per mile. This works because the course does not cover an even number of miles. -- Saifuddin S F Khomosi, Dubai
BUT GOOGLE THIS NOW
1. We all know that multiplication is addition in bulk and division is subtraction along similar lines. Thus we know that 4*4 is adding 4 four times and 16/4 is 4 times deducting 4 from 16. But how can we apply the same logic from the first principles as above in the case of a multiplication or division operation when both minus signs are involved as in (-4)*(-4) and (-16)/(-4)? (Submitted by Seshagiri Row Karry, srkarry@yahoo.com)2. Why can we not hear our heartbeats even though sound waves travel faster in solid media than in air and water? (Submitted by Chandrakant Deshpande, cddeshpande 2017@gmail.com)