1. (2,1) is the point which is twice as far from P as from Q.
2. Out of 1 - 7 leave 1, 2 and 3, since their divisibility is covered in 6. Hence the remaining ones are 7, 6, 5 and 4. consider 7 and 6, 42 is the lowest number which is divisible by 7 and 6. Coming down to 5, 42 is not divisible by 5, but multiplying it by 5 makes it so. hence the no. is 210. come to 4, this is still not divisible by 4. The minimum value we multiply by 210 so as to make it divisible by 4 is 2. i.e. 420. Which is the lowest number divisible by numbers 1 - 7.
I am pretty sure that there would be a short cut for this kind of question. May be some one can post that tooo :)