Friday, 21 September 2018

DAY 458

How do you equally divide three oranges among four people?

Answer:

Each person gets 3/4 of an orange. Cut each orange into quarters and give each person three.

Wednesday, 19 September 2018

DAY 457

Matchstick Puzzle

The equation below in Roman numerals (9-12 = 3) is obviously wrong. Move one line (matchstick) to produce a correct equation. (The solution does not involve an inequality sign, negative numbers, or changing an X to a V.)

IX - XII = III

HINT:
There are 13 lines in the equation.

Answer:

IX = XII - III
















Friday, 14 September 2018

DAY 456

From Reader's Digest

If it cost one cent to ride 1,000 miles, how much would a trip around the world cost? How much to go to the moon? The sun? And how much would it cost to go to Alpha Centauri, our nearest star other than the sun. Use the following distances to help solve:


Circumference of the Earth: 25,000 miles
Distance to the moon: 240,000 miles
Distance to the sun: 93,000,000 miles
Distance to Alpha Centauri: 26,000,000,000,000 miles
                                             (26 trillion - 4.2 light years)

Answers:

25 cents to go around the Earth
$2.40 to go to the moon
$930 to go to the sun
$260,000,000 to go to Alpha Centauri

Explanation of the math:

Think of the distances as multiplied by 1,000 - to give the number of cents. Then translate the number of cents into dollars by dividing by 100 (if necessary).

Earth - circumference of 25,000 miles - 25 thousands = 25 cents

Moon - 240,000 miles from Earth - 240 thousands = 240 cents = $2.40

Sun - 93,000,000 miles from Earth - 93,000 thousands = 93,000 cents = $930

Alpha Centauri - 26,000,000,000,000 miles from Earth
                              26,000,000,000 thousands
                              26,000,000,000 cents = $260,000,000 

Note from JA: Alpha Centauri's distance at 26 trillion miles can also be expressed as 4.2 light years. 

Wednesday, 29 August 2018

DAY 455

What do you get if you divide the circumference of your jack-o-lantern by its diameter?

Answer:

Pumpkin pi

Monday, 12 February 2018

DAY 454

TWENTY-FOUR

Credit: Jon Erickson
HACKING
The Art of Exploitation, 2nd Ed.

Use each of the numbers 1, 3, 4, and 6 once and only once with any of the four math operations to total 24. You may define the order of operations. For example, 3 x (4+6) + 1 = 31 is valid, but incorrect, since it doesn't total 24.
                                                       
[Note from JA: This problem is not nearly as simple as it might appear. You'll appreciate the solution more if you try it first - before looking at the hints or answer.]

HINTS:
1. There are no parentheses, exponents, or radicals in the answer.
2. The answer involves only two math operations.
3. The answer involves fractions.
4. The answer involves division of fractions.

Answer:

[Note from JA: I was able to figure out that the answer had to involve division of fractions. I also figured out that 6 divided by 1/4 would equal 24. But what about that pesky 3? This is where I gave up. Here is the solution:] 

      
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