The diameter of a spherical grapefruit is 6.0 inches. An amateur fruit slicer misses its center by one inch. What is the radius of the circular slice?

2 answers

draw a side view.
Draw a circle
Mark a vertical diameter
Draw a horizontal radius from the center O
The radius has length 3
Draw another vertical line 1 unit away from the center.
On that vertical line, mark its intersections with the horizontal radius (A) and the circle (B).

Then you have a right triangle OAB.

OA^2 + AB^2 = OB^2
1^2 + AB^2 = 3^2

AB^2 = 8
AB = √8

Note that AB is the radius of the sliced section.
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