#16 Clever code
Rashmi told us that she had to make up some codes, ones that preferably have a unique quality to them.
鈥淔or a four-digit code, I chose 2020, because it has two 0s, zero 1s, two 2s and zero 3s. I chose 3211000 for a seven-digit code.鈥�
She then told us that she used the same idea for a 10-digit code.
What was this code?
Answer next week
#15 Lines through the chessboard
Solution
It is possible to cut through all 64 squares with seven lines. There are several ways to do it, but here is one approach. In fact, it is always possible to draw lines through an NxN grid with no more than N-1 lines.
Quick quiz #15
1 The area around Solnhofen in Bavaria, Germany, is the source of all 12 fossil specimens of which pioneering flying creature?
2 In 2015 to 2016, Mark stayed on the ground while Scott orbited Earth on the International Space Station. What were they up to?
3 If you douse yourself in beta-ionone, you are liable to come up smelling of what?
4 Amphibians, reptiles and most birds use a single orifice for urination, defecation and sexual reproduction. What is it called?
5 Underlying Fort Worth and surrounding areas of Texas, which geological formation is thought to contain the largest reserves of any onshore natural gas field in the US?
Answers below
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Quick quiz #15
Answers
1 Archaeopteryx
2 Investigating the effect of space flight on the body 鈥� the Kelly brothers are identical twins and are both astronauts
3 Roses
4 The cloaca. Some male birds also have a penis to aid the reproductive process
5 The Barnett Shale