# Algebra - check to see if correct

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**help please**
.

Telephoto lens. Use the formula from Exercise 67 to find the image distance i for an object that is 2,000,000 mm from a 250-mm telephoto lens. (Section 6.7 (1/f = 1/0 +1/i)

1/i = 1/250 - 1/ (2*10^9)

i=25.