Answer :
The distance of the object is 18.6cm.
How to find the object's distance?
According to lens formula we have (1)/(v) + (1)/(u) = (1)/(f), where u = distance of the object from the lens, v = distance of the image from the lens and f = focal length of given lens.
1 / v + 1 /u = 1/f
1 / 15 + 1 /u = 1/77.5
1/77.5 - 1 / 15 = 1/f
1/f = 6 / 465 - 31 / 465
1/f = -25 / 465
1/f = 465 / 25
1/f = 18.6
Lens formula is a well-designed formula that is applicable for concave as well as convex lenses.
Learn more about the Lens formula here: brainly.com/question/2098689
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