Two cars race around a circular track, in opposite directions, at constant rates. They start at the same point and meet every 30 seconds. If they move in the same direction, they meet every 120 seconds. If the track is 1800 metres long, what is the speed of each car?Hint1)Let x = rate of car […]
A cunning farmer, when asked how many sheep he has, replied, “One-third of my sheep are in the barn, and one-fifth are in the pasture. Three times the difference between these two numbers equals the amount of newborns. My daughter has one as a pet.”How many sheep does the farmer have? Answer15.5 in the barn,
The local CD shop operates an unusual discount policy. The discount on the next purchase is worked out on the current purchase in the following way: for every whole dollar spent you get 0.5% discount on the next purchase. For example, if you purchased $8.99 on the first purchase, you would then get a 4%
Sarah, Daniel, Megan and Shawn are each collecting Terrible Toby, Jumping James and Super Scout comic books. Together they have 100 comic books and everyone has at least one. Daniel has 3 times as many as Megan. Sarah has twice as many as Daniel and Shawn has fewer than 40.Who has the most comics? AnswerSarah
With a blank ruler (without marks) of exactly 13 cm you can only measure 13 cm. Now you are allowed to set 4 marks so that you may read off all full centimetre values from 1 to 13 cm directly from the ruler.Where must these 4 marks be?Much harder question:The blank ruler has a length
My computer has been up to its usual tricks again. I wanted to know the population of some major countries and here are the results:USA 1,30,000England 4,10,000France 3,40,000Peru 2,00,000Brazil 3,40,000Greece 3,00,000Japan 2,70,000How many people were listed as living in Tibet? Answer270,000 people.Each vowel is worth 3 and each consonant is worth 7; these are added
Jeff has a bunch of coins. Figure out how many coins he has using only these facts:He puts an equal amount in each of 9 bags and has none left over.He puts an equal amount in each of 6 bags and has none left over.He puts an equal amount in each of 5 bags and
Glenn’s step is 4 fifths of that of his father’s and he walks 30 steps in a minute.Glenn’s sister, Melanie has a step which is 3 quarters of Glenn’s and walks 25 steps in a minute.Glenn’s mother has a step which is twice the size of Melanie’s and walks 20 steps in a minute, but
A farmer wants to sell sheep at a fair which lies on the other side of the hill under which he lives. In order to get there in time, he needs to travel at an average speed of 60km/h. The road is 10km up the hill and 10km down the hill. However, his car can
Dad wants one-cent, two-cent, three-cent, five-cent, and ten-cent stamps. He said to get four each of two sorts and three each of the others, but I’ve forgotten which. He gave me exactly enough to buy them; just these dimes. How many stamps of each type does Dad want? A dime is worth ten cents. AnswerThe
You have a group of eighty-two men. Some of the men are tall, the number of the medium-height men is double that of the tall men and the number of the short men is triple that of the medium-height men and one man is very tall. You know that all tall men are bald but
A bookworm eats from the first page of encyclopaedia number 1 to the last page of encyclopaedia number 5. The bookworm eats in a straight line. Each encyclopaedia consists of 400 pages. Each leaf is 0.01 inch thick and each cover is 0.25 inch thick. What distance does the bookworm eat through? AnswerThe bookworm nibbles
Peter had 144 books and donated them to four schools. When Peter checked the number of books given to each school, he found out that the difference of the number of books between School A and School B was 4; between School B and School C was 3; between School C and School D was
The Principal of Jimbo’s school interviewed 30% of the 8th graders at recess about the food fight yesterday. The Assistant Principal grabbed 40% of the 8th graders at lunchtime to investigate the disappearance of all of the blackboard erasers. Fortunately for Jimbo, he was in the 50% of the 8th graders that escaped without an
Two cars circumnavigate the world. Time is kept as they pass each other, travelling in opposite directions at the same speed of 70 miles per hour. The only difference is that one car is travelling on the surface of the planet, while the other is on a roadway 15 feet above ground.Assuming the world is