How many 4-digit numbers greater than 3000 can be formed from the digits 1,2,3,4,5 if repetition is allowed? 

From a deck of cards, what is the probability of drawing a heart or a face card (J, Q, K)? 

In a group of 50 students, 30 like Math, 25 like Science, and 10 like both. If a student is chosen at random, what is the probability they like neither Math nor Science? 

 A PIN code consists of 3 different digits followed by 2 different letters. How many such codes can be formed? 

If 𝑃(𝐴)=0.3, 𝑃(𝐵)=0.5, and 𝑃(𝐴∩𝐵)=0.1, find 𝑃(𝐴∪𝐵)