4th order dark fringe and 2nd order bright fring spaced 2.5cm apart appear on the screen placed 1 m behind the double slit. What is the spacing of the slits if the waveleght of incident light is 500nm?

x=2.5cm=.025m
L=1m
wavelegth= 500nm = 5x10^-7m
d=?

x/L=wavelength/d
d= (wavelegth)(L)/x
=5x10^-7m*1m/ .025
= 2x10^-5m

Is this correct?