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Two numbers between 1 and 30 inclusive are drawn in a contest. What is the probability that both numbers are even?
I believe there are 15 even and 15 odd numbers.
The chance of first card being even is 15/30
The chance of second card being even is 14/29
so i think we should multiply these two numbers and I get 7/29.
But the solution says
15/30 x 15/30 = 1/4.
Am I wrong?
Another question I have is...
if it says how many numbers are there between 0 to 10,
do we include both 0 and 10 thus total of 11 numbers or
do we just count 1~9 without including 0 and 10?
I believe there are 15 even and 15 odd numbers.
The chance of first card being even is 15/30
The chance of second card being even is 14/29
so i think we should multiply these two numbers and I get 7/29.
But the solution says
15/30 x 15/30 = 1/4.
Am I wrong?
Another question I have is...
if it says how many numbers are there between 0 to 10,
do we include both 0 and 10 thus total of 11 numbers or
do we just count 1~9 without including 0 and 10?