Author Topic: Maths help... u know who I am :D  (Read 2540 times)

holtadit

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Maths help... u know who I am :D
« on: April 02, 2010, 02:48:18 pm »
Question 5  b  iv

The MS says 1/18   how is this possible ?

Question 10  b i                 -------> How do u get the formula ?
Question 10 b iii a              -------->  MS says 16, how ? 




The MS and Question paper are attached..


Offline astarmathsandphysics

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Re: Maths help... u know who I am :D
« Reply #1 on: April 02, 2010, 03:20:05 pm »
b)i)A=5xy=80 so xy=16 and y=16/x
P=10x+2y =10x+2*16/x=10x+32/x
b)iii)a) xy=16  and x=y so x^2=16 and x=y=4
P=10x+32/x=10*4+32/4=48

Offline astarmathsandphysics

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Re: Maths help... u know who I am :D
« Reply #2 on: April 02, 2010, 03:23:42 pm »
I dont have the ms can you upload it?

Offline Ghost Of Highbury

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Re: Maths help... u know who I am :D
« Reply #3 on: April 19, 2010, 06:26:41 pm »
5 b iv ) The options are Sarah gets 1 and Terry gets (1+4) = 5
                                       
                                     or
                                 Sarah gets 2 and terry gets (2+4) = 6

The probability now

for the first Sarah gets 1 = 1/6  ; Terry gets 5 = 1/6 . Total = because of "And" --> 1/6 * 1/6 = 1/36

for the second one Sarah gets 2 = 1/6 ; Terry gets 6 = 1/6. Total = because of "And" --> 1/6 * 1/6 = 1/36

Due to the "or" we add the two sets up = 1/36 + 1/36 = 2/36 = 1/18
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