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Subject :IMO    Class : Class 8

Ans 1:

Class : Class 9
x+1/x=4 So,(x+1/x)^2=4^2=16 x^2+2+1/x^2=16 Since (x-1/x)^2=x^2-2+1/x^2, It will be=(x+1/x)^2-4=16-4=12 So, (x-1/x)=√12 Which is equal to √2×2×3 =2√3

Ans 2:

Class : Class 9
x+1/x=4 So,(x+1/x)^2=4^2=16 x^2+2+1/x^2=16 Since (x-1/x)^2=x^2-2+1/x^2, It will be=(x+1/x)^2-4=16-4=12 So, (x-1/x)=√12 Which is equal to √2×2×3 =2√3

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Subject :IMO    Class : Class 3

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Subject :IMO    Class : Class 6

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Subject :IMO    Class : Class 4

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Subject :IMO    Class : Class 4

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Subject :IMO    Class : Class 4

Ans 1:

Class : Class 4
Answer is c

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Subject :IMO    Class : Class 6

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Subject :IMO    Class : Class 6

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Subject :IMO    Class : Class 6

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Subject :IMO    Class : Class 7

Ans 1:

Class : Class 8
Let the initial numbers be x, then 5:3 becomes 5x/3x. then, 5x-10 divided by 3x-10 equals 5x divided by 7x. so the equation becomes: 7 (5x-10) = 5(3x-10). solve it and you get x=1 Therefore the sum of 5:3 is 8.

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