Well we are a little late in revealing the answers to the last Maths trivia, but nevertheless we got couple of people who did get it right.

If you are wondering what the trivia was about? We had asked our readers a question to tell us the combination of currency notes that make up $100 with 50 notes, none of those 50 notes could include a $2 note in it.

Before I tell you the answers there were two people who got it right. Congratulations both of you.

1. Ankesh Kothari
2. Rich Fiege

Here are the answers to those, well answers because there are two of it;

Answer 1:

• 40 notes of $1 = $40
• 8 notes of $5 = $40
• 2 notes of $10 = $20

Answer 2:

• 45 notes of $1 = $45
• 3 notes of $5 = $15
• 2 notes of $20 = $40

Well that’s it for this week, hope you enjoyed the trivia this time. Look forward to more people answering it in the next week.

We have always enjoyed playing maths games with users and if you have not been following us we have had a maths trick that guessed your age and also told you about the way it is done. While your at it you may also want to check out few amazing facts about alphabets and numbers or just see how interesting a little bit of mathematics can turn out to be.

Well to not let our new readers away from the excitement here is a new trivia which we want you to solve for this week, answers for it will be posted on Wednesday with special mentions to whoever gets it right, so go ahead rack your brain and tell us how intelligent you are.

The Trivia

A person has $100 ($ is used for representation purpose) in the form of 50 paper currency notes. In the 50 notes the person has, there are no $2 notes at all. We want to know what combination of notes the user has in his pocket that will bring up a total of $100.

Trivia Notes / Tips: Only $1, $5, $10, $20, $50 and $100 are accepted as valid currencies. You cannot use $2 notes to create the combination.

Go ahead tell us your combinations, we are looking forward to how intelligent brains work.

If you studied hard at school you may remember Algebra well lets do some algebra magic out here to crack the solution for yesterday’s post on how I can figure out your age without you telling me, if you have not read that yet read it first and come back to view the solution.

The Answer

Assume ‘x’ to be any number that you want it may be a single digit number or a double digit number or a triple digit number. The final outcome would depend on the number of digits you choose so if you choose single digit number the final outcome will be a 3 digit number, for a double digit number the outcome will be a 4 digit number and so on.

Of course a 0 will result in an output of 2 digit number.

Next Step: Multiply it by 2
Output: 2x

Next Step: Add 5 to it
Output: 2x + 5

Next Step: Multiply it by 50
Output: 100x + 250

Let’s Ponder

At this stage it is quite certain that you will always get a result of 250 even if you have chosen 0 as the first age, lets keep the 100x aside for a bit and look at the numbers 1756 and 1757.

Adding up 250 and 1757 results to 2007 and adding up 250 and 1756 results to 2006, that is year lesser than this year.

Now if your birthday hasn’t passed it is quite obvious that your age is that as of 2006 and if it has passed it is that as of 2007. Now the claim that this will only work in 2007 is partly correct. This will work in any year if you change the number 1756 and 1757 to a number that on adding to 250 give you the current year and previous year.

So assuming its 2010 the numbers would be 2010 – 250 = 1760, for those whose birthdays have not yet passed you have subtract one from 1760, so the two numbers to be used in 2010 will be 1759 and 1760.

Example for year 2010

3 x 2 = 6 + 5 = 11 * 50 = 550 + 1759 = 2309 – 1982 = 327

Now the last two numbers is my age in 2010.

You need to use 5 and 50 because the other two numbers 1757 and 1756 add up to give you a result which is the current year or the previous year for those whose birthday’s are not yet passed for the year. 

You can use practically any numbers to get the same results that end up in showing you your current age. For example using 6 as the base and 10 as the multiplier the other two numbers that would be used is 1947 and 1946 which is subtracted from the current year by 60.

Converting this logic into a simple algebra expression

Current year = c, basenum = b, multiple = m, x is the number to subract, y is the number to subtract if the birthday has not passed this year

x = c – (b * m)

y = c – (b * m) – 1

Simple isn’t it.

Now the mystery 100x?

What we learnt above is the base of solving the mystery, but the bigger mystery is how can any random number fetch accurate results. That part of the mystery is the 100x formula.

The number you choose does not make and difference, the outcome will always be 100x, so if you choose 2 the outcome would be 200, if you choose 3 the outcome would be 300 and so on.

Lets analyze the trend with the final results.

If you chose 1. Outcome will be 2107
If you chose 2. Outcome will be 2207
If you chose 3. Outcome will be 2307
If you chose 4. Outcome will be 2407
If you chose 5. Outcome will be 2507
If you chose 6. Outcome will be 2607
If you chose 7. Outcome will be 2707
If you chose 8. Outcome will be 2807
If you chose 9. Outcome will be 2907

Now there are two trends out here which we will look at one is that subtracting the 100x output will from the final output will always give you the current year, here is how the simplified formula looks like assuming x is the number you choose and current year is y and z is your final output after doing all the above calculation.

y = z – 100x;

Another trend that you will notice is that since it is multiplying x by 100 the resultant output would be x00 always.

The age guessing trick

When you subtract your birth year from the output you are always left with a output similar to xYY where x is the number you chose and YY is your age, since we already know that 100x will always result in multiples of 100 the subtraction of your birth year is always performed on the current year adding up your age to 100x.

The final formula is assuming z is your birth year

YY = ( ((x * 2) + 5 + 1757) + 100x ) – z;

The result of the formula will always be xYY, where x is the number you chose and YY is your current age.

Simple isn’t it, no wonder there are so many maths fanatics around. I loved solving this trick and it turned out to be a interesting thing after all. Ashish from Technospot.net came very close to the actual formula.

Well do let me know your thoughts on it by adding your valuable comments.

Just follow this cool little trick and I will be able to ascertain your actual age without you telling me

1. How many times do you eat your dinner in a restaurant in a week.
2. Now take this answer and multiply it with 2.
3. Add 5 to it.
4. Multiply the result with 50.
5. If this year your birthday has already passed this year add 1756 to the total, if it has already passed add 1757.
6. Now subtract the year you were born in from the total, so if you were born in 1960, subtract 1960 from the above total.

If you do not eat your dinner out at all you will only see a 2 digit number as the final results. If you go outside at least once a week to have your dinner you will get a three digit number as the final output.

Examples

Your birthday hasn’t passed this year yet and you eat dinner 3 times a week outside

now 3 x 2 = 6 + 5 = 11 * 50 = 550 + 1756 = 2306 – 1982 = 324

Your birthday has passed this year and you do not eat dinner outside at all

now 0 x 2 = 0 + 5 = 5 * 5- = 550 + 1757 = 2007 – 1982 = 25

The Surprise

Ok now the surprise, in the first example the first number out of the 3 digit number is the number of times you go out for dinner in a restaurant in a week and the last two digits is your current age.

In the second example since you do not eat my dinner out even once a week you got only two digits as the final result and the two digits that come up is your current age.

Go ahead do it yourself and tell me if it works or not.

Awesome isn’t it, well this was forwarded to me as a email but I figured out how this is able to figure out the exact age, well though the suspense will not be revealed today it will be done tomorrow, till then you have time to rack up your brain and think of the answer.

This trick is supposed to work only in the year 2007 but I have figured out how to do it for other forthcoming years too.

Do not forget to tell me your thoughts or answers on how this is done with your comments. Tomorrow I will reveal the answers.

Mathematics has always been a brainchild to so many things that have evolved in life, its a under statement that some mathematic calculations lead to amazing combinations in its own.

Well with amazing i do mean that they are amazing combinations used, the Fibonacci series is one of them, but how many such series do exist do we even know about them, here are few series which lead to an amazing amount of curiosity what numbers can do.

I found this through CuriousMath just wondering how many such combinations do exist, your inputs are always welcome, but still have a look at some amazing combinations numbers can perform.

3 x 37 = 111 and 1 + 1 + 1 = 3
6 x 37 = 222 and 2 + 2 + 2 = 6
9 x 37 = 333 and 3 + 3 + 3 = 9
12 x 37 = 444 and 4 + 4 + 4 = 12
15 x 37 = 555 and 5 + 5 + 5 = 15
18 x 37 = 666 and 6 + 6 + 6 = 18
21 x 37 = 777 and 7 + 7 + 7 = 21
24 x 37 = 888 and 8 + 8 + 8 = 24
27 x 37 = 999 and 9 + 9 + 9 = 27

1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321
11111111 x 11111111 = 123456787654321
111111111 x 111111111 = 12345678987654321

1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 +10 = 1111111111

9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888

1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321

7 x 7 = 49
67 x 67 = 4489
667 x 667 = 444889
6667 x 6667 = 44448889
66667 x 66667 = 4444488889
666667 x 666667 = 444444888889
6666667 x 6666667 = 44444448888889

and so on

4 x 4 = 16
34 x 34 = 1156
334 x 334 = 111556
3334 x 3334 = 11115556
33334 x 33334 = 1111155556

Do you have your own mathematical combinations that have left you awe struck, you can comment them here its always awesome.

Via: CuriousMath