842. Dr. Plex is the proud owner of two ancient mummies. His colleagues are testing him. One mummy is painted red on both sides. The other is red on one side and white on the other side. They randomly select a mummy, and Plex can see only the top surface, which turns out to be red. What is the probability that the other side is red? If Plex is a gambler, should he bet that the other side is red?
844. What 2 words, formed from different arrangements of the same seven letters,
can be used to complete the sentence below?
Two hundred years ago, wild bar ________ in some port cities were often interrupted by ________ who kidnapped customers as coin.
846. Mary was working in a chemistry lab with a mixture of chemicals that was 90 percent water and weighed 20 pounds (equal portions of water and the chemical mixture weigh the same). After returning to the lab from a weekend break, Mary calculated the mixture which was now 50 percent water. How much does the mixture now weigh? (For purposed of this puzzle, assume the non-water part of the mixture is not affected by evaporation).
853. Mr. Hobbs, the math teacher, has separated a list of numbers
into two lists. Can you determine what criterion he used to separate the numbers?
1, 23, 57, 117, 12555, 222, 3
14, 263, 857, 1179, 1205, 888
855. Find the six-digit number in which the first and last digits are the same and each is three times the second and twice the third; the fourth digit is double the second; and the fifth is the sum of the second and third.