Nails and Feathers
Nails and Feathers
If you have a pound of nails and a pound of feathers which one weighs more?
There weigh the same because there both are a pound.
Math Riddles
Reveal Answer
Juggling the jugs
Juggling the jugs
If you want to measure out exactly one pint of water, and you have only a three pint jug and a five pint jug. How would you do it?
Fill the three pint jug with water and pour it into the five pint jug. Then fill the three pint jug with water once again, and pour it into the five pint jug until it is completely full. The water remaining in the three pint jug is one pint.
Mind Bender 12
Mind Bender 12
A singer has twice as mant pants as pairs of shoes in her wardrobe and three-halves as many t-shirts as pants. What is the least number of items she can have in her wardrobe in order to make a different shoes, pants, and T-shirt combinations for each day of the year. (Hint: Try using a tree diagram) Show All work.
Let P=pants
S=shoes
T=T-shirts
P*t*s=Answer
S=shoes
T=T-shirts
P*t*s=Answer
Four members of a band …
Four members of a band …
Four members of a band are walking to a night concert. They decide to take a shortcut, but must cross a bridge. Luckily they have one flashlight.
Because of the varying size of their instruments, it takes each member a different amount of time to cross the bridge – it takes the first person one minute, the second person two minutes, the third person five minutes and the fourth person ten minutes.
They must cross the bridge in pairs, travelling at the slower speed so if the one minute person went with the ten minute person, it would take a total of ten minutes.
Since there is only one flashlight, one person must come back across the bridge, then another pair can cross.
They only have 17 minutes to cross the bridge and still get to the concert on time. What order should they cross to get everyone across and get to the concert?
First, the one minute person and the two minute person must cross the bridge, for a total of two minutes. Then the one minute person should come back with flashlight - total of three minutes. The five minute person and the ten minute person cross together next, making the total thirteen minutes. Now the two minute person goes back and (total now fifteen minutes) and gets the one minute person and they cross together bringing the total to seventeen minutes.
Crayons in a box
Crayons in a box
There is a mixture of purple, orange, and yellow crayons in a crayon box. The total number of crayons is 60, there are four times as many orange crayons as yellow crayons. There are also 6 more purple crayons than orange crayons. How many crayons of each color are there?
there are 30 purple crayons,24 orange crayons and 6 yellow crayons.
Age of father and son
Age of father and son
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).
51 and 15. 42 and 24. 60 and 06.
One Through Nine
One Through Nine
How can you make 100 using the numbers 1 to 9 only once each?
9*8+7+6+5+4+3+2+1 = 100
Crack me up
Crack me up
you have 7 crackers on the table and you take away three of them. How many crackers do you now have?
3- you took three of them
the cigars
the cigars
Two fathers and two sons just closed a great deal and to celebrate, they go to the cigare store to buy some fine cuban cigars. However the store only has three cigars in stock, and yet they all leave with a cigare. How is this possible?
There is a grandfather, a father and a son
Crushed fly
Crushed fly
Two trains 200 miles apart are moving toward each other; each one is going at a speed of 50 miles per hour. A fly starting on the front end of one of them flies back and forth between them at a rate of 75 miles an hour. It does this until the trains collide and crush the fly to death. What is the total distance the fly has flown?
Since the trains are 200 miles apart and each train is going at 50 miles an hour, it takes 2 hours for the trains to collide. Therefore the fly was flying for 2 hours. Since the fly was flying at the rate of 75 miles per hour, then the fly must have flown 150 miles.
three coins
three coins
you have three american coins and one of them is not a fifty cent pice, what are the coins?
the coins are two quarters and a fifty cent peice...how can this be??? because the question said only one isnt a fifty cent peice so you have two other coins to chose from.
Two hospitals
Two hospitals
A certain town is served by two hospitals. In the larger hospital, about 45 babies are born each day. In the smaller one, about 15 babies are born each day. Although the overall proportion of girls is about 50%, the actual proportion at either hospital may be greater or less on any day. At the end of a year, which hospital will have the greater number of days on which more than 60% of the babies born were girls?
The answer is 2: the smaller hospital. The Law of Large Numbers says:
The more people we survey, the more accurate the result.
Larger samples are better.
In this case, the number of children born each day is a random sample of the number of children born in a year. There is much more deviation in a small (daily, in this case) sample than over an entire year. Similarly, there will be more deviation in a sample of size 15 than in one of size 45. Even though both hospitals will have about 50% girls over the year, the smaller hospital will have more days in which the number is higher than 60% (and more days when it is less than 40%). (Consider the extreme case of a hospital that has one baby a day. Every day will be either more than 60% girls (one) or less than 40% girls (zero).
People commonly and mistakenly believe that even very small samples will have the same composition as large ones. Remember this next time someone uses a small survey sample to "prove" something -- the results may be invalid!
The more people we survey, the more accurate the result.
Larger samples are better.
In this case, the number of children born each day is a random sample of the number of children born in a year. There is much more deviation in a small (daily, in this case) sample than over an entire year. Similarly, there will be more deviation in a sample of size 15 than in one of size 45. Even though both hospitals will have about 50% girls over the year, the smaller hospital will have more days in which the number is higher than 60% (and more days when it is less than 40%). (Consider the extreme case of a hospital that has one baby a day. Every day will be either more than 60% girls (one) or less than 40% girls (zero).
People commonly and mistakenly believe that even very small samples will have the same composition as large ones. Remember this next time someone uses a small survey sample to "prove" something -- the results may be invalid!