Question

Ravi starts for his school at 8:20a.m. on his bicycle . If he travels at a speed of 10km/hr then he reaches his school late by 8 mins but on travelling at 16km/hr he reaches the school 10 mins early . At what does the school start ??

Answer 1

Given that Ravi starts for his school at 8:20 am 

Let the distance be x km

(1) Given that he travels at a speed of 10km/hr and reaches by 8 minutes late.

x/10=y+8/60

x+10=y+2/15------(1)

(2) Given that he travels at a speed of 16km/hr and reaches by 10minutes             early .

x/16=y-10/60
x/16= y-16---------(2)


On solving (1) and (2) , we get 

x/10 - x/16 = 2/15 + 1/6

3x/30 = 9/30 

x=9* 80/30 * 30

  = 8 km-------(3)

Substitute (3) in (2) , we get  

8/16 = y- 1/6
 
y - 1/6 = 8/16

y - 1/6 = 1/2

y = 1/6 + 1/2

   = 2/3 hours

   = 2/3 * 60

y = 40 minutes 

Ravi starts school at  8:20 am + 40 minutes =9:00 am.
 
His school starts at 9:00 am .



HOPE IT HELPS  AND MARK THIS AS  BRAINLEIST............

Answer 2

$\huge {\green {\sf {\underline {\underline{Solution}}}:-}}$

Let "t" minutes are required to reach school from home on time when Ravi starts at 8 : 20 a.m.

Distance= (t + 8) 10 = 16 (t - 10)

Distance = Time × Speed

10 t + 80 = 16 t - 160

6t = 80 + 160

$t = \frac{240}{6}$

t = 40

Hence, school starts from forty minutes after 8:20 a.m. i.e., from 9:00 a.m.

$\huge\dag\sf\red{By \: Divyanshu}$