I have this: A person threw a standard dice three times. He obtained two distinct odd prime numbers in two throws and an even number which is not a factor of 18 in the third throw. The sum of all the numbers on the opposite faces of numbers obtained in the three rows is? ( Answer : 9 )
In this, It is given, He obtained two distinct odd prime numbers in two throws Distinct odd prime numbers in a dice are 3 i.e., 1,3 and 5
And an even number which is not a factor of 18 in the third throw So the number will be 4.
But how do I find the sum of all numbers on the opposite faces of numbers in three rows? A supportive explaination would do great:)
The sum of a face with its opposite face is always $7$. So we have that the opposite faces of $3$, $5$ and $4$ are $4$, $2$ and $3$ respectively. From there we have the answer: $4+2+3=9$.