For the coin: 2 possibilities, either head or tail. So probability of head is 1/2.
For the cube (assuming numbers are 1 to 6): 6 possibilities (1 2 3 4 5 6). We have 3 odd numbers, so probability of odd number is 3/6=1/2.
You want both head and an odd number, so you multiply the 2 probabilities: 1/2×1/2=1/4.
So the answer is 1/4.
You can use a tree to better understand probabilities.
