I'm completely lost with this question.

Numerical question: In a class of 20 students, 10 reported sleeping late over the weekend, 13 reported exercising, and 3 reported doing neither. The 10 students who slept late may or may not have also exercised. Similarly, the 13 students who exercised may or may not have also slept late. If we select a student at random from the class, the probability that he or she both slept late and exercised is . (Express the probability as a decimal number between 0 and 1, not as a percentage, i.e., write a number with two decimal places; do not include words or calculations.)