Exams › SSC CGL (Prelims) › General

If two circles touch externally, how many common tangents do they have?

1. 1
2. 2
3. 3
4. 4

Correct answer: 3

Solution

Two separate circles have four common tangents. When they touch externally, the two internal tangents coincide at the point of contact, reducing the total to three. Therefore, externally touching circles have 3 common tangents.

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