equations..help!

[rissagurlie]

rearrange this formula so that N is by itself on one side.

this is what i have

E=1.96(.25/N)^(1/2)

/1.96 /1.96

E/1.96=(.25/N)^(1/2)

(E/1.96)^(2)=(.25/N)

1/[(E/1.96)^(2)] = (N/.25)

 

[happy]

Don't double post!

http://www.mathgoodies.com/forums/topic ... C_ID=25950

 

[Denis]

rearrange this formula so that N is by itself on one side.
this is what i have
E=1.96(.25/N)^(1/2)
/1.96 /1.96
E/1.96=(.25/N)^(1/2)
(E/1.96)^(2)=(.25/N)
1/[(E/1.96)^(2)] = (N/.25)

Rewrite for clarity:
E = 1.96 * sqrt(.25 / N)

E / 1.96 = sqrt(.25 / N) : divide by 1.96

E^2 / (1.96)^2 = .25 / N : square both sides; sqrt(a) squared = a

N(E^2) = .25(1.96)^2 : crisscross multiplication

N = [.25(1.96)^2] / E^2 : divide by E^2