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10=2[0]+0+9
9=(2x0x0)+9
7= -2.00+9
(Sorry, I don’t know how to type an exponent. The 10 equation is supposed to start with 2 to the 0 power.)
jewishfeminist02-
So far you’re doing well – keep going.
The carat character (^) is Shift+6 on most fonts. Alternately you can use the character map utility (on a windows pc).
(please take a few moments to say some tehilim for those in Mumbai)
ICanOnlyTry and Jfem you are out of my league – I hate maths.
Here’s a nice and easy one
My life can be measured in hours,
I serve by being devoured,
Thin, I am quick,
Fat, I am slow,
Wind is my foe.
What am I?
Here’s a toughie:
How many female names (in Loshon Kodesh/Hebrew) can you name, that has a gematria of 646?
(Sorry, no hints till theres an answer!)
Nobody, I too hate math- just thought I would try my hand at this one, since unlike traditional math problems, there seem to be multiple correct answers.
As for your riddle…is it a candle?
ICOT, it took me a while to come up with those three…let’s see what else I can think of. I’m certain I’m forgetting some math function or expression that would help (haven’t taken secular classes in nine months, so I guess I’m a little rusty.) Okay, I got one:
6=(2+0+0)Sq9 [How do you type a square root???]
So that still leaves 1,2,3,4, and 8, since you provided 5. I’ll keep thinking.
will hill,
I AM A GUY! i stink at math though so i have no idea
ICOT,
Thanks for clarifying that for Dr. Pepper. I’ve made it clear in other threads that I’m female, so I figured he knew.
I apologize if I offended anyone, with out even thinking I put a title of Reb out of respect for my fellow Yidden, but I’ll stop.
“I can only try”
In the future feel free to ask any math questions, and please don’t think you are taking advantage- I’m here to help.
Here’s how the rule works, (if you know of anyway that I can attach a PDF file to a post or somehow upload a file somewhere that I can link here please let me know. This is hard to follow without mathematical formatting).
2x + y + z = 3
x + 2y + z = 0
Given the general form of a system of three linear equations with three unknown variables:
ax + by +cz = j,
da + ey + fz = k,
ga + hy + iz = l
put this in matrix form:
a b c
d e f
g h i
(3 x 3 matrix)
multiplied by
x
y
z
(3 x 1 matrix)
equals
j
k
l
(3 x 1 matrix)
x =
the determinant of:
j b c
k e f
l h i
divided by
the determinant of:
a b c
d e f
g h i
(The determinant of a 3 x 3 matrix
a b c
d e f
g h i
For our example:
a = 2, b = 1, c = 1, j = 3
d = 1, e = -1, f = -1, k = 0
g = 1, h = 2, i = 1, l = 0
therefore the determinant of
j b c
k e f
l h i
is the determinant of
3 1 1
0 -1 -1
0 2 1
= 3
the determinant of
a b c
d e f
g h i
is the determinant of
2 1 1
1 -1 -1
1 2 1
= -2 -1 + 2 +1 +4 -1
= 3
therefore x = 3/3 = 1.
Similarly
y =
the determinant of:
a j c
d k f
g l i
divided by
the determinant of:
a b c
d e f
g h i
and
z =
the determinant of:
a b j
d e k
g h l
divided by
the determinant of:
a b c
d e f
g h i
The final results are x = 1, y = -2 and z = 3.
I hope this helps.
Dr. Pepper,
I wasn’t in the least offended, and I see no need to stop addressing people that way. I think ICOT mentioned it because some posters prefer to know the gender of the person they’re addressing.
Correction, Gentleman:
The correct riddle is thus;
How many male names (in Loshon Kodesh/Hebrew) can you name, that has a gematria of 646?
Hint: The name might contain 6 characters.
will hill: how about some specific parshios? or at least chumashim.
or any part of tanach
Jfem02 Gold Star to you! Yey!!!
Dr Pepper – you are kidding aren’t you? Are we supposed to follow this?
Okay, I have an alternative solution for 9. I racked my brains and remembered eighth-grade algebra- good old FOIL! Too bad it doesn’t give me a new answer.
9=(2-0)(0+9)
I probably should have defined some terms.
A matrix is a rectangular array (m by n) of numbers. It can be a single number (a 1 by 1 matrix) or any other dimension (m and n must be positive integers). A matrix is denoted by brackets on both sides.
A determinant is a value only given to a square matrix (where m = n). For a 1 by 1 matrix the determinant is the lone entry. For a 2 by 2 matrix
a b
c d
the determinant is (a)*(d)-(c)*(b).
The formula for a 3 by 3 matrix was mentioned above in my previous post.
Please don’t ask me to post the formulas for anything greater than m = n = 3, they are very long.
The determinant of a matrix is denoted by vertical bars on both sides. For example if we have a matrix named “A” then the determinant of “A” is denoted by |A|. There are also text books that put the vertical bars on both sides of the whole array to denote the determinant.
I can only try
0 = 2*0*0*9
1 = 2^0+0*9
2 = 2+0*0*9
3 = 2*0*0+?9
4 = 2^0+0+?9
5 = 2+0+0+?9
6 = (2+0+0)*?9
7 = -2+0+0+9
8 = -(2^0)+0+9
9 = 2*0*0+9
10 = 2^0+0+9
Nobody
If there’s something you don’t understand please ask. I’m here to help. I understand that it may be hard to follow because of the formatting but I wouldn’t consider this example challenging.
Happy New Year:
jewishfeminist02-
not bad at all
Dr. Pepper-
Correct!
Time and Again solution:
1) 5 (that I came up with)
3)
Water, Water Everywhere
Yankel, a U.S. Army Corps of Engineers employee, was assigned the task of reconstructing the New Orleans levees.
On what Hebrew calendar date(s) should Yankel take his measurements?
Why?
Boy’s name with a gematria of 646? ______
Will Hill,
whats with you and the personel questions?
and can you answer the question i asked you in both the thred about girls learning and the random questions thread?
Riddle: A maskil that starts with a “triple-0”: ______
will hill: from tanach, or in general??
cuz here i am, killing myself thru every parsha lol
Bym, in general (though maybe Tanach, but not necessarily.)
Few hints:
Maybe 6 letters.
Kuf = 100
Resih = 200
Shin/Sin = 300
Tuf = 400
So there is only a few ways to get to 600 something. (e.g. Shin & Shin…, Tuf & Kuf…, etc.)
last example should’ve read tuf and reish. (these are just possibilities thrown out…)
Water, Water Everywhere: Answer
At the very beginning/end and in the very middle of the Hebrew month, right at chatzos (either day or night).
These are the times that the sun, earth, and moon most closely line up in a straight line, so the gravitational pulls of the sun and the moon work together to cause high tide.
That is so neat ICOT… never thought about that.. would the season make any difference? (except not during the late summers when there are hurricanes… kind of hard to do…) this riddle page is neat for finding odd facts!
Havesomeseiche-
There are other factors as well, such as planetary alignment, but the effect of other planets on our tides is very minor.
(from an IQ test)
15, 8, 12, 80
18, 7, 6, 147
19, 6, 12, ?
An Easy One (for political junkies)
According to a Gallup poll, the U.S. president was the most-admired man in America in each of the following years, except one.
Which one?
Why?
a) 1986
b) 1979
c) 1974
d) 1970
e) 1966
ICOT
Even though LBJ was really unpopular, I’m guessing 1974 – the year of Nixon’s whole scandal. (that WAS 1974, right?!?)
brooklyn19-
Correct!
yeah well i’m not such a math person but history?!?! bring it on!
Each man actually paid $9 (after receiving $1 change) so altogether that makes $27 plus the $2 that the waiter kept makes $29. What happened to the last $1?
You are in a house with an all-southern view. Suddenly, a bear walks by. What color was the bear?
I posted the same riddle as above to a different audience a few years ago. It met with much lively discussion:
A bear drops into a hole in the ground from v=0 meters per second at time t = 0. Two seconds later it landed on the bottom. If the hole is 20 meters deep and we assume no air resistance, what color was the bear?
15, 8, 12, 80 ==> 15 x 2 x 8^2 / (12 x 2) = 80
18, 7, 6, 147 ==> 18 x 2 x 7^2 / (6 x 2) = 147
19, 6, 12, ? ==> 19 x 2 x 6^2 / (12 x 2) = 57
Squeak-
By the time the falling bear hits the bottom of a 60-meter pit, it will be traveling at about 43-44 mph.
At that speed, whether it was originally black or white, it is probably now red all over.
I can only try
Why the extra steps?
This is how I would do it:
15, 8, 12, 80 ==> 15 x 8^2 / 12 = 80
18, 7, 6, 147 ==> 18 x 7^2 / 6 = 147
19, 6, 12, ? ==> 19 x 6^2 / 12 = 57
Squeak-
Here’s an old one:
In the following equation, what Yom Tov does x equal to: 10^x = baomer?
(It was taken from the secular riddle 10^x = cabin.)
Dr. Pepper-
I held off on posting the solution, because I was sure you’d get it and were just waiting in order to give others a chance.
You are correct, of course, but I wanted to associate a “2” with each number (except the result).
To you, was this “two” puzzle too easy? Et, tu?
Dr. Pepper-
Cute – it’s been a long time since 10th grade geometry 😉
I can only try
I actually thought I got it after the first line but I was wrong.
I did 1 x 5 x 8 x 1 x 2 = 80.
But no!
Next I found the prime factorizations and got almost nowhere on the first line (except that I found many instances of the number 2) but on the second line there was one 7 on the left side and two on the right so I knew that one of the terms was squared.
The rest was smooth sailing.
One day, a person went to horse racing area, Instead of counting the number of human and horses, he instead counted 74 heads and 196 legs. Yet he knew the number of humans and horses there. How did he do it, and how many humans and horses are there?
What place in this world can have their temperatures Fahrenheit and Celsius equal?
Joseph,
Let X = humans and Y = Horses
X + Y = 74
2 * X + 4 * Y = 196 => X + 2 * Y = 98 (divide both sides by 2)
(X + 2 * Y = 98)
-(X + Y = 74)
=> Y = 24 => X = 50
50 Humans and 24 Horses.
Joseph,
-40 degrees Celsius = -40 degrees Fahrenheit
I think the North Pole would be one place.
This isn’t a riddle but a neat math trick my daughter figured out several years ago. If you take 2 numbers, x and x+2, their product will be one less than the square of their average. For example, 6×8=48, which is 1 less than the square of 7, or 49. This makes it easy to figure out a product like 19×21, since it’s just 20^2-1, or 400-1=399. If all of you already knew this, I apologize, but I thought it was neat (you can use polynomials to prove why this works).
A variation on this makes it easier to figure out the square of a number like 4.5. The answer is (4×5)+.25 or 20.25.
If anyone is interested I can post the proof. Or I can just leave it as an exercise for the reader (I always felt like this was a copout when I saw it in a textbook but it’s fun to write).
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