5.4. Ivan Ivanovich's age is 48 years 48 months 48 weeks 48 days 48 hours. How many full years old is Ivan Ivanovich? Don't forget to explain your answer.
Answer: 53 years.

48 months is 4 years, 48 weeks is 336 days, 48 days and 48 hours is 50 days, in total 53 years and 21 or 20 days, hence the answer.

Comment. Correct answer only - 3 points; answer with explanations or calculations leading to the answer - 7 points.