Question

You randomly pick two numbers from 1 to 9 (including 1 and 9). A number that is chosen once could be chosen again. If at least one of the two numbers is odd and less than 5, what is the probability that their sum will be less than 5?

Answer 1

Assume that you only include whole numbers (1,2,3,4,5,6,7,8,9) and not 3.5 and such
so if 1 is odd and less than 5 then it is
1 or 3, since 5 isn't included
then the other number, to be less than 5 when added,
must be
1+x<5
3+x<5
solve each
1+x<5
subtract 1
x<4
set of answers are 1,2,3

3+x<5
subtract 3
x<2
set of answer is 1
so the possible numbers are
1,2,3
that is 3 numbesr out of 9 so
probability=(total desired outcomes)/(total possible outcomes) so
disred outcomes=3
total possible=9
3/9=1/3
the probabiltiy is 1/3