Whats Probability of getting a number less than 5 and a head when rolling a die, then tossing a coin

The probility of getting a number less than 5 is 4/6 or reduced it is 2/3. The probility of getting a head is 1/2. Since these are independent events and you are wanting to meet both requirements, you need to multiply the two results so you multiply 2/3 * 1/2 and get 2/6 which reduces to 1/3.

You have a 10 percent chance on the dice