so yeah... someone asked me this number riddle/question. ""What number's double exceeds it's half by exactally 99?" . Im sure its REALLY easy..but im really bad with anything dealing with numbers.
My first thought was 99 ..because It seems to me that the double of 99...exeeds 99 by 99 but he says thats wrong..... but maybe im totally missing something. Lol that and im just horrible at anything with numbers. Help please?
(this wasnt hw but i didnt know where else to put it)
2006-10-25 13:33:01 · 11 answers · asked by swyftsilver84 2 in Education & Reference ➔ Homework Help
66
2006-10-25 13:37:10 · answer #1 · answered by NeRdYkId1101 3 · 1⤊ 0⤋
You're a little close just flip 99 and you get the answer ... 66 !
It's simple algebra that can help you solve this riddle.
Let x = the number, 2x is double the number, (1/2)x is half the number.
If the double exceeds the half by 99, then the equation is:
2x = (1/2)x + 99
Multiply everything by 2 to get rid of the fraction (1/2) and you get
4x = x + 198 .... combine like terms so subtract x from both sides
3x = 198 ... divide both sides by 3 to solve for x, the number
x = 66
To check
Does double of 66 exceed half of 66 by exactly 99?
Plug back in equation ...
2(66) = (1/2)(66) + 99
132 = 33 + 99
132 = 132 ... CHECK! =) I hope this was clear. :)
2006-10-25 13:41:28 · answer #2 · answered by PuzzledStudent 2 · 0⤊ 0⤋
Let the number be x
Then 2x - (x/2) = 99
4x - x = 99 * 2
3x = 99 * 2
x = 66
Check
(66 * 2) - 33 = 132 - 33 = 99
2006-10-25 13:37:54 · answer #3 · answered by Anonymous · 2⤊ 0⤋
Try 99
2006-10-25 13:35:45 · answer #4 · answered by lizataggiecattoni 1 · 0⤊ 0⤋
66
2006-10-25 13:40:41 · answer #5 · answered by Stephanie73 6 · 0⤊ 0⤋
66
if we call the number X
we know that 2x = 1/2X + 99
Therefore x = 66
2x66 =132
1/2X = 33
The difference between the two is 99
2006-10-25 13:42:28 · answer #6 · answered by angie 5 · 0⤊ 0⤋
2x - 99 = x/2
4x - 198 = x
-198 = -3x
198 = 3x
x = 66
2006-10-25 13:42:13 · answer #7 · answered by Anonymous · 0⤊ 0⤋
I don't get it either, I'm not much of a riddle person. But I can safely say that that person has poor level of english, making it harder to understand.
2006-10-25 13:37:00 · answer #8 · answered by krunkee1 2 · 0⤊ 0⤋
.5x+99=2x
99=1.5x
99/1.5=x
66=x
2006-10-25 13:39:38 · answer #9 · answered by Sydney 2 · 0⤊ 0⤋
66! God I can still do algebra!
2006-10-25 13:44:30 · answer #10 · answered by madammeow69 2 · 0⤊ 0⤋