Out of 40 consecutive integers two are chosen at random Find the probability that their sum is even

even+even=even
odd+odd=even
40 consecutive integer will have 20 even and 20 odd numbers.
20/40*19/39+20/40*19/39
10 years agoHelpfull: Yes(7) No(1)
19/39
either to choose 2 odd no or 2 even thn sum will b even
20c2+20c2/40c2
10 years agoHelpfull: Yes(4) No(0)
Forty consecutive integers will have 20 even and 20 odd integers. The sum of 2 chosen integers will be odd, only if:
First is even and second is odd
First is odd and second is even
Mathematically the probability will be given by:
P(First is even) * P(Second is odd) + P(First is odd) + P(Second is even)

= (20/40) * (20/39) + (20/40) * (20/39)

= 20/39
10 years agoHelpfull: Yes(2) No(2)
20/40*20/39 + 20/40*20/39
10 years agoHelpfull: Yes(0) No(1)
ans:-20c2/40c2+20c2/40c2
10 years agoHelpfull: Yes(0) No(0)

Out of 40 consecutive integers, two are chosen at random. Find the probability that their sum is even?