Three Kinds of Apples

Three kinds of apples are mixed randomly in a box. How many apples must you take out to be sure of having at least two apples of one kind?

Four. If the apples are A, B, and C, it’s possible that you could take out one A, one B and one C with three apples, but the fourth apple must be one of the three kinds.

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Starts With T

What starts with a T, ends with a T, and has “T” in it?

A teapot.

Posted in Riddles

I’m Yours, But Used More By Others

I belong to you, but am used more by others.

What am I?

Your name. It could also be your phone number.

Posted in Riddles

Money Is Right Above My Reach

Money is right above my reach, I’m barely staying out of The Emergency Room (It is right below me), Room #3 is to my left, Room #5 is to my right with a 5% interest rate.

What am I?

The number 4 key on a QWERTY keyboard. $ is money, ER (an abbreviation for Emergency Room) are the two letters immediately below the number 4 key, the #/3 key is to the left and the 5/% key is to the right.

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The More You Leave Behind

The more you take, the more you leave behind.

Footsteps or footprints.

Posted in Riddles

Beam, Shine and Sparkle White

I beam, shine and sparkle white,
I brighten the day with a single light.
I charm and enchant one and all,
I can counter the darkest pall.

What am I?

A smile.

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Mario’s Racing Grandma

Mario is testing out a new car at the racetrack. His grandmother took it for a mile lap and averaged 30mph. How fast does Mario have to drive in the second lap to average 60mph for the two miles?

90mph is an alluring answer, but it’s impossible. At 90mph the second lap would take 40 seconds. If Grannie’s first lap at 30mph took 2 minutes, traveling 2 miles in 2 minutes and 40 seconds is an average speed of 45mph. Traveling an average speed of 60mph for 2 miles would take 2 minutes and since the grandma’s lap took all of those 2 minutes, even if Mario could break the sound barrier he wouldn’t be able to average 60mph.

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Stands

Stands
———–
0_2345

What does this represent?

No one understands.

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Largest Product

Using all the digits from 1 to 7, what two numbers have the largest product? For example, 1234 x 567 = 699678 but you can do much better than that.

742 x 6531 = 4,846,002.

A similar problem can be found in L.A. Graham’s Ingenious Mathematical Problems and Methods with a range of 1 to 9, but the principle remains the same – the numbers with the smallest difference produce the largest product. You start out with the highest two digits, 7 and 6, then attach 5 and 4, putting the smaller of the two digits with the larger number, giving you 74 and 65. The next two highest digits are 3 and 2, giving you 742 and 653. Finally, you add the 1 to the lower number. Page 80 has the details of that solution.

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Frederick’s Epitaph

Frederick died after a long and productive life of 87 years, but this epitaph was written on his headstone:

Frederick lived a good long life,
He loved his children and his wife,

He was honest, kind and deserved nothing but praise,
Even if he only had twenty-one birthdays.

How is this possible?

He was born on February 29th in a leap year. Consequently, in his 87 years, he only witnessed twenty-one of his actual birthdays. The other years there was no February 29th.

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