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    How do answer this Biology question? michaels

    Lens E is marked 10× and lens O is marked 40×.

    A cell is viewed through lenses E and O.

    The image of the cell is 0.8 mm in diameter.

    What is the actual diameter of the cell?

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      Total magnification of 400x which means that the image you are seeing is 400 times the actual size. This "magnified" image is 0.8mm so the "original/actual" image must be 400 times smaller than this (0.8mm/400).

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      because you are looking through both lenses the total magnification is 400 (10x40). At magnification 400 the cell has a diameter of 0.8mm, so to find what the diameter is with no magnification you must divide 0.8 by 400. :)

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      To find the magnification of a cell you multiply the lens powers, here it is 10x and 40x. Therefor, the final magnification will be 400x ( See x as magnified 400 times).

      Now 400times of an object makes it 0.8mm in diameter.

      That is,

      400y = 0.8;

      y = 0.8/400

      y = 0.002mm

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