TYS 'O' LVL maths question

• tinuviel07

  13 Oct 08, 22:32

  to add on to part (a).

   

  squares can be positive x positive or negative x negative

• lpx88

  13 Oct 08, 22:33

  Originally posted by gunner77:

  wah dont understand..........

  which part?

• gunner77

  13 Oct 08, 22:33

  Originally posted by lpx88:

  which part?

  
  every part.

  the part a got 2 answer.

• tinuviel07

  13 Oct 08, 22:34

  Originally posted by gunner77:

  
  every part.

  the part a got 2 answer.

  haha ask him to edit based on my earlier post.. i go watch tv first

• gunner77

  13 Oct 08, 22:35

  Originally posted by tinuviel07:

  haha ask him to edit based on my earlier post.. i go watch tv first

  
  after u watch tv help me ok?

• lpx88

  13 Oct 08, 22:35

  Originally posted by gunner77:

  
  every part.

  the part a got 2 answer.

  Part A got 2 answers becoz when u square root a number, the answer is valid both negative and positive forms.

   

  Eg (-4)^2 =16

  (4)^2=16 as well

• gunner77

  13 Oct 08, 22:37

  Originally posted by lpx88:

  Part A got 2 answers becoz when u square root a number, the answer is valid both negative and positive forms.

   

  Eg (-4)^2 =16

  (4)^2=16 as well

  
  i understand how u get 3.5

  but i don understand how to get -0.5

• lpx88

  13 Oct 08, 22:38

  -0.5 is the answer we derive when we get (2a-3) = - 4 as well

   

  U key in yr calculator :-4 X -4. give u how much?

  16 also right? So (2a-3) = -4 as well

  since we know 2a-3=-4

  2a= -4+3 =-1

  a=-1/2= -0.5

• gunner77

  13 Oct 08, 22:40

  Originally posted by lpx88:

  -0.5 is the answer we derive when we get (2a-3) = - 4 as well

   

  U key in yr calculator :-4 X -4. give u how much?

  16 also right? So (2a-3) = -4 as well

  since we know 2a-3=-4

  2a= -4+3 =-1

  a=-1/2= -0.5

  ohh !! yaya !

  how come i dint tink of tat?!

  thanks

  can u explain part B too?

  i thought the equation should be y= Kx^2

                         K is the constant

• lpx88

  13 Oct 08, 22:43

  Originally posted by gunner77:

  ohh !! yaya !

  how come i dint tink of tat?!

  thanks

  can u explain part B too?

  i thought the equation should be y= Kx^2

                         K is the constant

  yea y=kx^2

  in this case k is 1 since they said Y is DIRECTLY proportional to X^2

  pardon me if im wrong,nvr touch these concepts for a year alrdy... but that's how i interpret the question and will solve it la =x

• gunner77

  13 Oct 08, 22:45

  errr... still confused

  i don understand ur steps where u get 400%

• lpx88

  13 Oct 08, 22:51

  Originally posted by gunner77:

  errr... still confused

  i don understand ur steps where u get 400%

  For me i will just sub in X for any value, and then increase its value by 100% to get the %change in why

  When we have X as 1, Y=1

  Later we increase X by 100%, from 1 becomes 2 what. Since 100% is 1. Increase by 100%, means increase by 1. 1+1=2

  As X is 2, Y =X^2 =4

  Compare the two values of Y for % change

  4/1 X100% =400%

  Not sure if this is the standard method to get the answer though.

   

  OH WAIT IT IS NOT!!!

  Y=X^2

  At 1st X is just..well X

  If it increases by 100%, X+X becomes 2X.

  With this new value, Y = (2X)^2 = 4X^2

  (4X^2/ X^2) X 100% =400%

   

  Which 1 u can understand better?

• gunner77

  13 Oct 08, 22:55

  wah headache..

  nvm nvm i go ask my friend.

  anyway thanks ah!

• lpx88

  13 Oct 08, 22:59

  Originally posted by gunner77:

  wah headache..

  nvm nvm i go ask my friend.

  anyway thanks ah!

  heh no prob. sry if my exp aint too good

   

  whens yr paper?

• tinuviel07

  13 Oct 08, 23:00

  need help?

• gunner77

  13 Oct 08, 23:02

  Originally posted by lpx88:

  heh no prob. sry if my exp aint too good

   

  whens yr paper?

  
  u mean maths paper?

• gunner77

  13 Oct 08, 23:03

  Originally posted by tinuviel07:

  need help?

  
  tin tin wat time u sleeping?

  i wan watch amazing race

  can i ask u later?

• tinuviel07

  13 Oct 08, 23:03

  see how lor.. not sure what time sleeping..

• lpx88

  13 Oct 08, 23:04

  Originally posted by gunner77:

  
  u mean maths paper?

  yea.

• gunner77

  13 Oct 08, 23:06

  ok ok

  i post. this question are easy but i have doubts about it

  13(a) the value of a house increased from $250000 to $600000

             calculate the percentage increase in the value of the house

  13(b) $20000 is invested in an account which pays 1% per month compound interset.

            FInd the total  amount in the account at the end of 3 months

• gunner77

  13 Oct 08, 23:07

  anwers

  (a) 140%

  (b) $26620

• gunner77

  13 Oct 08, 23:09

  Originally posted by lpx88:

  yea.

  
  maths p1 is 24th oct

  maths p2 is 30th oct

  tats why now i practise p1 first

• tinuviel07

  13 Oct 08, 23:11

  Originally posted by gunner77:

  ok ok

  i post. this question are easy but i have doubts about it

  13(a) the value of a house increased from $250000 to $600000

             calculate the percentage increase in the value of the house

  13(b) $20000 is invested in an account which pays 1% compound intereset.

            FInd the total  amount in the account at the end of 3 months

  (a) (600K - 250K)/250K x 100% = 350k/250k = 140%

  (B) 1% interest per annum right or..

   

   

• gunner77

  13 Oct 08, 23:13

  Originally posted by tinuviel07:

  (a) (600K - 250K)/250K x 100% = 350k/250k = 140%

  (B) 1% interest per annum right or..

   

   

  
  B) sorry its per month.

• tinuviel07

  13 Oct 08, 23:26

  u sure ur qn nothing wrong