Question: There are two ropes that both take exactly 1 hour to burn from end to end. You are unable to cut the rope. How can you burn the two ropes in a total of 45 minutes?
Answer: Start one of the ropes on fire from both ends and the other one from one end. After a half an hour one rope will be completely burnt and the other will be half burnt. At this point you light the final rope from the unlit side and it will take 15 minutes for the remaining half of the rope to burn, for a total of 45 minutes.
Question: 8,549,176,320 What makes this number unique?
Answer: The said number has all the numbers from 0-9 exactly once and what is special is they are in lexicographical order of their English words. Where 8,549,176,320 becomes eight-five-four-nine-one-seven-six-three-two-zero. ... The number contains all the digits from 0 to 9.
Question: Hard, Harder, and Hardest are brothers. By age from youngest to oldest, it goes Hard, Harder, Hardest. Hard is half the age of Hardest who is 20 which means hard is 10. Harder has a two-year difference between the number of years older he is than Hard and the number of years younger he is than Hardest. Harder is closer to the age of Hard than Hardest. How old is Harder?