Basic HTML Version

|  | Table of Contents |  | View Full Version

Page 188 - Touchpad Mathematics_Ver1.0_C4
P. 188

    E:\Working\Orange_Education\TouchPad_Maths_4\Open_Files\Chap_11\Chap_11
                 \ 10-Nov-2025  Bharat Arora   Proof-8                                     Reader’s Sign _______________________ Date __________

                Time duRATion

                The time  taken  to  finish an activity  is called its  duration. Some  activities  can be

                completed in minutes and some in hours. If we know the starting time and finishing
                time of an activity, we can find its duration.

                example 1. Garima left for school at 7:20 a.m. and reached school at 7:50 a.m. How
                much time did Garima take to reach school?

                Solution. Duration from 7:20 a.m. to 7:30 a.m. = 10 minutes

                Duration from 7:30 a.m. to 7:50 a.m. = 20 minutes

                Total duration = 10 minutes + 20 minutes = 30 minutes

                Thus, Garima took 30 minutes to reach school.

                example 2. A bus left Ghaziabad at 5:40 p.m. and reached Delhi at 6:25 p.m. How

                much time did the bus take to reach Delhi from Ghaziabad?
                Solution. Duration from 5:40 p.m. to 6:00 p.m. = 20 minutes

                Duration from 6:00 p.m. to 6:25 p.m. = 25 minutes

                Total duration = 20 minutes + 25 minutes = 45 minutes

                Thus, the bus took 45 minutes to reach Delhi from Ghaziabad.

                example 3. Deepak’s school starts at 8:10 a.m. and ends at 1:40 p.m. How long does

                the school work?
                Solution. We find the duration from 8:10 a.m. to 1:40 p.m. as shown below:

                Duration from 8:10 a.m. to 9:00 a.m. = 50 minutes

                Duration from 9:00 a.m. to 1:00 p.m. = 4 hours

                Duration from 1:00 p.m. to 1:40 p.m. = 40 minutes

                Total time duration = 4 hours 90 minutes
                    4 hours 90 minutes = 4 hours + 60 minutes + 30 minutes

                                             = 4 hours + 1 hour + 30 minutes
                                             = 5 hours + 30 minutes

                So, the school works for 5 hours 30 minutes.                                     1 hour = 60 minutes

                To Find the Finishing Time

                If we know the starting time and the duration of an activity, we can find its finishing

                time.

                       186       Mathematics 4

| 183 184 185 186 187 188 189 190 191 192 193 |