camera lens problem

[rubykap]

the dimensions of the picture on a 35mm color slide are 24X36 mm,an image of the slide is projected on a screen 9.00 m from the projector lens.the focal length of projectorlens is 150mm.
1-- how far is the slide from the lens
2-- what are the image on the screen.

Plz some body help me...i m not getting any clue

[Borek]

Do you know lens formula? Do you know intercept theorem?

[rubykap]

yes lens formula is
1/s + 1/s' = 1/ f

[Borek]

Just look at what you know and what you need for the 1st part... Simple algebra.