Samacheer Kalvi Class 5 Maths Solutions Term 1 Chapter 5 Time

Question 1. Write down your school timetable of the following:
a. Morning school break time to morning school ending time.
b. Morning school working time.
c. Afternoon school working time.
d. Afternoon Lunch break time.
Answer:
a. Morning school break time to morning school ending time
Morning school ending time = 12 hours 40 minutes
Morning School break time = 11:00 hours
Morning school break time to Morning school ending time = 12 hours 40 minutes - 11:00 hours = 1 hour 40 minutes

So, the duration from morning break time to school ending time is 1 hour and 40 minutes.
b. Morning school working time
Morning school class time = 12 hours 40 minutes
Morning school first bell = 9 hours 30 minutes
Morning school working time = 12 hours 40 minutes - 9 hours 30 minutes = 3 hours 10 minutes

Thus, the morning school working time is 3 hours and 10 minutes.
c. Afternoon school working time
Evening school closing time = 4 hours 10 minutes
Starting time = 2:00 hours
Afternoon school working time = 4 hours 10 minutes - 2:00 hours = 2 hours 10 minutes

Therefore, the afternoon school working time is 2 hours and 10 minutes.
d. Afternoon Lunch break time
Lunch time = 14 hours (which is 2:00 p.m. in 24-hour format)
Afternoon Lunch break time calculation:

Afternoon Lunch break time = 1 hour 20 minutes. Timetables help organize our day and make sure everything runs smoothly.
In simple words: We calculated how long each part of the school day lasts by subtracting the start time from the end time.

🎯 Exam Tip: When calculating durations, always convert times to a consistent format (e.g., 24-hour clock) to avoid errors, especially when crossing noon or midnight.

Question 2. Match the following
Answer:

To convert from 12-hour to 24-hour format, for p.m. times (except 12 p.m.), we add 12 to the hour. For a.m. times, the hour remains the same.
In simple words: We changed the times from the usual 12-hour clock (with a.m. and p.m.) to the 24-hour clock format.

🎯 Exam Tip: Remember that "12 p.m." is 12:00 hours in 24-hour format, and times like "1 p.m." become "13:00 hours" by adding 12.

Question 3. Addition
a. 4 hours 30 minutes + 2 hours 50 minutes =
b. 4 hours 50 minutes + 2 hours 30 minutes =
c. 3 hours 45 minutes + 1 hours 35 minutes =
d. 1 hours 50 minutes + 3 hours 45 minutes =
e. 2 hours 25 minutes + 4 hours 50 minutes =
Answer:
a. 4 hours 30 minutes + 2 hours 50 minutes

4 hours 30 minutes + 2 hours 50 minutes = 7 hours 20 minutes.
b. 4 hours 50 minutes + 2 hours 30 minutes

4 hours 50 minutes + 2 hours 30 minutes = 7 hours 20 minutes.
c. 3 hours 45 minutes + 1 hours 35 minutes

3 hours 45 minutes + 1 hours 35 minutes = 5 hours 20 minutes.
d. 1 hours 50 minutes + 3 hours 45 minutes

1 hours 50 minutes + 3 hours 45 minutes = 5 hours 35 minutes.
e. 2 hours 25 minutes + 4 hours 50 minutes

2 hours 25 minutes + 4 hours 50 minutes = 7 hours 15 minutes. It is important to remember that there are 60 minutes in one hour when performing these calculations.
In simple words: We added hours and minutes. If the minutes add up to more than 60, we change 60 minutes into 1 hour and add it to the hours.

🎯 Exam Tip: When adding time, always remember to regroup minutes into hours when the minute sum is 60 or greater, by dividing the total minutes by 60.

Question 4. Subtract
a. 5 hours 10 minutes - 2 hours 35 minutes =
b. 4 hours 20 minutes - 2 hours 40 minutes =
c. 4 hours 25 minutes - 1 hours 20 minutes =
d. 6 hours 55 minutes - 2 hours 20 minutes =
e. 5 hours 45 minutes - 3 hours 55 minutes =
Answer:
a. 5 hours 10 minutes - 2 hours 35 minutes

5 hours 10 minutes - 2 hours 35 minutes = 2 hours 35 minutes.
b. 4 hours 20 minutes - 2 hours 40 minutes

4 hours 20 minutes - 2 hours 40 minutes = 1 hour 40 minutes.
c. 4 hours 25 minutes - 1 hours 20 minutes

4 hours 25 minutes - 1 hours 20 minutes = 3 hours 05 minutes.
d. 6 hours 55 minutes - 2 hours 20 minutes

6 hours 55 minutes - 2 hours 20 minutes = 4 hours 35 minutes.
e. 5 hours 45 minutes - 3 hours 55 minutes

5 hours 45 minutes - 3 hours 55 minutes = 1 hour 50 minutes. Subtracting time often requires borrowing an hour (60 minutes) from the hours column when the minutes to be subtracted are larger.
In simple words: We subtracted hours and minutes. If we need to take away more minutes than we have, we "borrow" 1 hour (which is 60 minutes) from the hour column.

🎯 Exam Tip: When subtracting time, if the minutes in the subtrahend (number being subtracted) are greater than the minutes in the minuend (number from which it's subtracted), borrow 1 hour (60 minutes) from the hours column and add it to the minutes column.

Question 5. Answer the following:
a. An office works from 10 a.m working hours? to 6 p.m What is the duration?
Answer:
Office closing time = 6 p.m. = 18:00 hours (in 24-hour format)
Office starting time = 10 a.m. = 10:00 hours (in 24-hour format)
Office working hours = 18:00 hours - 10:00 hours = 8:00 hours

The office working duration is 8 hours.
b. A school works from morning 9 O'clock to evening 4 O' Clock. What is the duration of working hours of the school?
Answer:
School closing time = 4 O'clock p.m. = 16:00 hours
Starting time = 9 O'clock a.m. = 9:00 hours
Working hours = 16:00 hours - 9:00 hours = 7:00 hours

The duration of school working hours is 7 hours.
c. A circus starts at 12:15 pm and ends by 2:30 pm. what is the duration of circus?
Answer:
Circus ending time = 2:30 p.m. = 14 hours 30 minutes
Circus Starting time = 12:15 p.m. = 12 hours 15 minutes
Duration = 14 hours 30 minutes - 12 hours 15 minutes = 2 hours 15 minutes. It's helpful to convert times to a 24-hour format for easier subtraction.
In simple words: We found how long the office, school, and circus were open by subtracting their start times from their end times.

🎯 Exam Tip: For problems involving time durations, always convert all times to a 24-hour format before performing calculations to avoid confusion with a.m. and p.m. and ensure accuracy.

Question 5.d. A bank works from morning 9:30 a.m. to 4:30 p.m. working time of the bank? [Subtract afternoon lunch break 1 hour to 2 hours]
Answer:
Bank closing time = 4:30 p.m. = 16 hours 30 minutes
Bank starting time = 9:30 a.m. = 9 hours 30 minutes
Total working time before lunch break = 16 hours 30 minutes - 9 hours 30 minutes = 7 hours 00 minutes

Lunch break = 1 hour 00 minutes
Actual working hour = Total working time - Lunch break
Actual working hour = 7 hours 00 minutes - 1 hour 00 minutes = 6 hours 00 minutes

The bank's working hours are 6 hours.
e. A man comes to his village in Tamilnadu from Ahmedabad. He travels 2 hours 15 minutes in Aeroplane and 4 hours 40 minutes in Car. What is the total time of travel?
Answer:
Hours taken by Aeroplane = 2 hours 15 minutes
Hours taken by car = 4 hours 40 minutes
Total Travelling time = 2 hours 15 minutes + 4 hours 40 minutes

Total Travelling time = 6 hours 55 minutes. Traveling by different modes of transport requires summing up their individual durations.
In simple words: First, we found the bank's total open hours and then subtracted the lunch break to find the actual working time. For the man's travel, we just added the time he spent on the aeroplane and in the car.

🎯 Exam Tip: When a question involves multiple time calculations (like working hours minus a break), break it down into smaller steps to ensure each part is calculated correctly before combining them.

Question 5.f. A painter paints a house for 3 hours 15 minutes in morning and 2 hours 50 minutes in evening. What is the total time he painted?
Answer:
Morning painting time = 3 hours 15 minutes
Evening painting time = 2 hours 50 minutes
Total hours = Morning painting time + Evening painting time
Total hours = 3 hours 15 minutes + 2 hours 50 minutes

The total time the painter painted is 6 hours 05 minutes. Adding time is a common real-world application of arithmetic.
In simple words: We added the time the painter worked in the morning and the time he worked in the evening to find his total painting time.

🎯 Exam Tip: When adding durations, always keep minutes separate from hours, add them, and then convert any minutes greater than 59 into hours to be added to the hours column.