Question

A car travels 3km in 5 minutes. Calculate the speed in @cm/s. @km/h.

Answer 1

Hey mate!!!!

1 km = 1,00,000cm
3 km = 3,00,000cm
1 minute= 60 sec
5 minutes= 300 sec

so 3km 5 minutes = 3,00,000/300 = 1000cm/s

Now second
km is already given
1 minute = 1/60 hr
5 minutes = 5/60 hr = 1/12 hr

now 3 ÷ 1/12 = 3 × 12 = 36km/hr

$\underline{Hope\: it\: helps \:dear\: friend }$

Answer 2

Hey Mate !

Here is your solution :

Given,

Distance travelled = 3 km

Time taken = 5 min

1. Calculate the speed in cm / s.

We know that,

=> 1 m = 100 cm --------- ( 1 )

" And "

=> 1000 m = 1 km

Plug the value of ( 1 ),

=> 100 cm × 1000 = 1 km

•°• 100,000 cm = 1 km

Now,

As , 1 km = 100,000 cm

•°• 3 km = 3 × 100,000 cm

= 300,000 cm ---------- ( 2 )

" And "

=> 1 min = 60

=> 5 min = 60 × 5 sec

•°• 5 min = 300 sec ---------- ( 3 )

Now,

Average speed = Distance travelled ÷ Time taken

= 3 km ÷ 5 min

Substitute the value of ( 2 ) and ( 3 ),

= ( 300,000 cm ) ÷ ( 300 sec )

= 1,000 cm/s

2. Calculate the speed in km/h.

Given,

Distance travelled = 3 km

Time taken = 5 min

We need to firstly convert time in h.

°•° 60 min = 1 h

•°• 1 min = ( 1/60 ) h

•°• 5 min = ( 5/60 ) hr = ( 1/12 )h ------ ( 1 )

Now,

=> Average speed = Distance travelled ÷ time taken

= 3 km ÷ 5 min

Plug the value of ( 1 ),

= ( 3 km ) ÷ ( 1/12 )h

= ( 3 × 12 km ) / h

= 36 km/h

================================

Hope it helps !! ^_^