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There are 25 points in a plane , of which 10 are on the same line.Of the rest,no 3 collinear and no 2 are collinear with any of the 1st 10 points.find the number of different straight lines that can be formed by joining these points

There are 25 points in a plane , of which 10 are on the same line.Of the rest,no 3 collinear and no 2 are collinear with any of the 1st 10 points.find the number of different straight lines that can be formed by joining these points

Grade:11

1 Answers

AKASH GOYAL AskiitiansExpert-IITD
419 Points
12 years ago

Dear Rahul

Total No. of straight line would be 25C2 but we have to subtract 10C2 because first 10 points will form a line.

So answer is 25C2-10C2+1=256

All the best

AKASH GOYAL
AskiitiansExpert-IITD

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