Calculating the Height of a Friend's Image from 4.2m Away

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To calculate the height of a friend's image from a distance of 4.2 meters, the correct approach involves using the ratio of distances (di/do) multiplied by the friend's actual height. The original attempt mistakenly included an incorrect distance value of 3.5 meters, which led to an incorrect calculation. Clarification on where the image is formed, such as on the retina, was also discussed. Ultimately, the user identified their mistake and expressed gratitude for the assistance received. Understanding the correct formula and values is crucial for accurate image height calculations.
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Homework Statement


Your friend is 1.7 m tall.

What is the height of her image when she is 4.2 m from you?


Homework Equations



I used di/do and multiplied that by the height of the friend

The Attempt at a Solution


I did (4.2/3.5)(1.7) but it was wrong. Not really sure what I'm doing wrong here.
 
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Where the image is formed? On the retina? What is 3.5 in your attempt?
 
nevermind I found my mistake. thanks for the help though
 

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