+4622 (1) What is the greatest number of points of intersection that can occur when 2 different circles and 2 different straight lines are drawn on the same piece of paper?
(2) Let p be a prime number between 40 and 60. What is the probability that p+12 is also a prime number? Express your answer as a common fraction
+129899 (1) I believe the answer to this is 11
The circles can intersect at 2 points
Each line can intersect each circle twice = 8 points
And as long as the lines do not intersect at any of the other points, they can intersect at 1 additional point
(2) Primes between 40 and 60 are
41 , 43 , 47, 53 , 59
And adding 12 to these =
53 , 55 , 59, 65 , 71
And 3 out of the 5 are prime [ 53, 59, 71 ]
So....the probability that p + 12 is prime is 3 / 5
