A boy presses a side of a blue pencil to a side of a yellow pencil, holding both pencils vertically. One inch of the pressed side of the blue pencil, measuring from its lower end, is smeared with paint. The yellow pencil is held steady while the boy slides the blue pencil down 1 inch, continueing to press it against the yellow one. He returns the blue pencil to its former position, then again it slides down 1 inch. He continues until he has lowered the blue pencil 5 times and raised it 5 times- 10 moves in all. Supposed that during this time the paint neither dries nor diminishes in quantity. How many inches of each pencil will be sneared with paint after the tenth move?
Think about the pattern of paint transfer between the two pencils with each move...
At the start, 1inch of the yellow pencil gets smeared with wet paint. As the blue pencil is moved downward, a second inch of the blue pencils smears a second inch of the yellow pencil. Each pair of down and up movesof the blue pencil smears 1 more inch of each pencil. 5 pairs of moves will smear 5 inches. This together with the initial inch, makes 6 inches for each pencil.
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How many sides does a circle have?
How many times can you subtract the number 5 from 25?
When John was six years old he hammered a nail into his favorite tree to mark his height. Ten years later at age sixteen, John returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be?
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What did one math book say to the other math book?
Lily is a lilypad in a small pond. Lilly doubles her size each day, On the 20th day she covers the whole pond. On what day was Lily half the size of the pond?
There is a clothing store in Bartlesville. The owner has devised his own method of pricing items. A vest costs $20, socks cost $25, a tie costs $15 and a blouse costs $30. Using the method, how much would a pair of underwear cost?
What did the triangle say to the circle?
One is to three as three is to five and five is to four and four is the magic number. What is the pattern?
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The ages of a father and son add up to 66. The father's age is the son's age reversed. How old could they be? (3 possible solutions).
What two whole, positive numbers have a one-digit answer when multiplied and a two-digit answer when added?
Pick a number from 1-10, multiply it by 2, add ten, divide it by 2, now subtract the number that you have from the number you picked. What is it?
You want to boil a two-minute egg. If you only have a three-minute timer (hourglass), a four-minute timer, and a five-minute timer, how can you boil the egg for only two minutes?
81 x 9 = 801. What must you do to make the this equation true?
How much will a 38° angle measure when looked at under a microscope that magnifies ten times?
If 1=5, 2=15, 3=215, and 4=3215. What does 5 equal?