A 27″ x 27″ square metal plate needs to be fixed by a carpenter onto a wooden board. The carpenter uses nails all along the edges of the square such that there are 28 nails on each side of the square. Each nail is at the same distance from the neighbouring nails. How many nails […]
Karin has two pencils. One is a good one, and the other is a cheap one. The good pencil cost $1.00 more than the cheap one. Karin spent $1.10 for both pencils. How much did her cheap pencil cost? AnswerFive cents. The expensive pencil cost $1.05. You may have thought the answer was 10 cents,
Both Tom and Tina have some money. Because it is a hot day, they decide to buy an ice cream for each of them. But then they realize they both don’t have enough money. Tom needs 24 cents more for his ice cream, and Tina needs two cents more to buy one. Now they decide
At midnight on Sunday, December 31st, Professor Lawrence set two of her analog clocks to the correct time. One of her clocks gains one minute every hour and the other loses two minutes every hour. When will the clocks next show the same time as each other? When will the clocks both show the correct
How many times do all the hands on a clock go around in an hour? AnswerSecond hand=60Minute hand=1Hour hand=1/12 Total: 61.083333
A rabbit and a kangaroo decided to have a race. Their course was 100 feet up and back (200 feet total). The rabbit only jumped in sets of three jumps of 2 feet each in the same time that the kangaroo only made two jumps of a yard each. Who won the race? AnswerThe rabbit
Which is the larger, the number of seconds in a week or the number of minutes in a year? AnswerThe number of seconds in a week is the larger.There are 6,04,800 seconds in a week, and 5,25,600 minutes in a calendar year.Note: There are 5,25,960 minutes in a leap year, which is still less than
Joan and Jane are sisters. Jean is Joan’s daughter and 12 years younger than her aunt. Joan is twice as old as Jean. Four years ago, Joan was the same age as Jane is now, and Jane was twice as old as her niece. How old is Jean? AnswerJoan is 32, Jane is 28, and
Maria doesn’t like to tell people her real age. When somebody asks her how old she is, she says that she is twenty-one. (Maria mentally omits all Sundays because on Sundays she doesn’t work, so she claims she doesn’t get any older.)How old is Maria really? AnswerMaria could be either 24 or 25. She subtracted
Jemal, Lara and Oren were making a giant sandcastle on the beach. They had 4 buckets: 2 red buckets that carry 3 lbs of sand each, 1 blue bucket that carries 5 lbs of sand, and 1 orange bucket that carries 7 lbs of sand.They took turns carrying full buckets of damp sand back to
Ten ice cream bars and 6 ice cream cones cost $13. But if you buy 6 ice cream bars and 10 ice cream cones, the bill will be $11. How much does an ice cream bar cost? AnswerIce cream bars cost $1. (Ice cream cones cost 50 cents.)
Martin rushed into the room bearing good news.“Joseph, your idea worked! The company liked the idea of using only two types of weights to measure heavy objects!” announced Martin, giving the letter to Joseph.“I told you so. Given any two types of weights, you can measure objects that are above a certain weight,” explained Joseph,
A block of wood, in the form of a cuboid 4″ x 7″ x 14″, has all its six faces painted pink. If the wooden block is cut into 392 cubes of 1″ x 1″ x 1″, how many of these would have pink paint on them? AnswerThe 1″ x 1″ x 1″ cubes that
The Boldavian navy has a rigorous training programme. In order to graduate from the naval academy, cadets must enter a pool and fight sharks. Today, a group of cadets was tested. Each cadet put on his mask, snorkel, two flippers; and armed himself with a knife. Then the cadets jumped into the pool. The sharks
Juanita was helping her mom and dad weed their garden. She noticed an interesting thing about the pea vines. No matter how tall they were, their leaves started one foot from the ground. Above that point, there was one leaf every four inches. The three vines in the garden were five, seven and eight feet