Question

Rita cycles to her school and leaves her house at 7:30a.m. If her speed is 9 km/h and the school is 600 metres away, at what time will she reach school?



Please solve this question ​

Answer 1

Answer:

if her speed is 9km/ h then it must be converted into m/s as

9km/h=9000/60×60s

=5m/2s=2.5m/s

now she has to reach 600 therefore

600 m is divided by 2.5m=240

so she has to travel with the same speed with next 240 second

240s=4min

therfore at 7:34 am she will reach her school

Answer 2

Answer :-

Reaching Time = 7 : 34 a.m

Solution :-

Leaving time of Rita = 7 : 30 a.m

Speed of cycle = 9 Km/h

Distance traveled = 600 m

Convert distance into Km

Divide speed with 1000

Distance in Km = 600/1000 = 6/10 Km

$\boxed{ \sf Speed = \dfrac{Distance}{Time} }$

Here

Speed (s) = 9 Km/h

Distance (d) = 6/10 Km

Time = t Hours

$\sf \implies 9 = \dfrac{ \frac{6}{10} }{t}$

$\sf \implies 9 = \dfrac{6}{10} \div t$

$\sf \implies 9 = \dfrac{6}{10} \times \dfrac{1}{t}$

$\sf \implies 9 = \dfrac{6}{10t}$

⇒ 9(10t) = 6

⇒ 90t = 6

⇒ t = 6/90

⇒ t = 2/30 hours

Covert time into minutes

Multiply time with 60

t (in minutes) = 2/30 * 60 = 120/30 = 12/3 = 4 minutes

Reaching Time = Leaving time of Rita + t (in minutes)

= 7 : 30 + 0 : 04

= 7 : 34 a.m

Therefore Reaching Time = 7 : 34 a.m