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Mystic
11-08-2004, 06:48 AM
Umm.......nobody answering my questions :(

OK here is one more , this is also from powerprep.

Hope I get this tonight

If n is an integer and 99<sqr(n)<200 then n could have at most how many values ?

() Two
() Four
()Six
()Eight
()Ten

Regards
M

calm_J
11-08-2004, 07:41 AM
hi
n =2

this is found from
99<n^2<200 then we can say 100<= n^2 < 200
then

10 <= n < 10 sqrt (2) this gives one value and
- 10 >= n > - 10 sqrt(2) this gives another value

bbm833
11-08-2004, 08:42 AM
You can calculate the square of numbers from 10 until you reach a number that is bigger than 200 :

10^2 = 100
11^2 = 121
12^2 = 144
13^2 = 169
14^2 = 196
15 ^2 = 225

as (-n)^2 = n^2

negative numbers should be considered.
Result set is -14, -13, -12, -11, -10, 10, 11, 12 , 13, 14

-->Answer is 10.

calm_J
11-08-2004, 09:01 AM
ohhh ooopppsss i missed to multiply 10* sqrt(2)
this means 14.1
whch gives 10 No.

Mystic
11-08-2004, 06:18 PM
Thanks!!!!!!!!

777
11-08-2004, 07:50 PM
Got 10 also.

As before:

10^2
.
.
.
19^2

is 10 integers, so n =10