Two standard six-sided dice numbered 1 to 6 are rolled. What is the probability that the product of the two numbers obtained is the square of a prime?
A)5/36
B)3/36
C)4/36
D) 6/36
E) 7/36
The answer should be A but i can’t tell what the 5th combination would be…
Break it into two pieces
First find the possibility of square of prime no
1×4=4=2^2
4×1=4=2^2
2×2=4=2^2
3×3=9=3^2
We cant take 4×4 because it becomes 16 and it is 4^2 and 4 is not prime number so
5×5=25=5^2
There are 6 sides so the possible outcome is 5 because we cant take square of 6 which become 36 and 6^2 and 6 is not prime no
And then six sided dice rolled twice so its total outcome is 36
=possible outcome/total outcome
=5/36
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