Question

Grandpa walks 1.5 km in 1 hour 20 minutes express speed metre per second also find how long would it take him to go from home to post office and return home if the distance between home and post offices 150 metres.​

Answer 1

Answer:

5/16 ; 480m

Pls mark as the brainliest :D

Answer 2

Grandpa speed is 5/16 m/s if  walks 1.5 km in 1 hour 20 minutes.

Time taken is 16 mins to go from home to post office and return home if the distance between home and post offices 150 metres.​

Given:

Grandpa walks 1.5 km in 1 hour 20 minutes

Distance between home and post offices 150 metres.​

To Find:

Express speed meter per second

Time taken to go from home to post office and return home

Solution:

1 km = 1000m

1 hr = 3600 secs

1 min = 60 sec

Speed = Distance / Time

Step 1:

Convert 1.5 km in m

1.5 x 1000 = 1500 m

Step 2:

Convert 1 hour 20 mins in secs

1 x 3600 + 20 x 60

= 3600 + 1200

= 4800 sec

Step 3:

Use formula for speed and calculate speed

Speed = Distance / Time

Speed = 1500/4800

Speed = 5/16 m/s

Step 4:

Find to and fro distance

150 + 150 = 300 m

Step 5:

Find time

Time =  Distance / speed

Time =  300/(5/16)

Time = 960 sec = 16 mins

Grandpa speed is 5/16 m/s if  walks 1.5 km in 1 hour 20 minutes.

Time taken is 16 mins to go from home to post office and return home if the distance between home and post offices 150 metres.​