Question

A boy walking at a speed of 20 km/h reaches his school 30 min late. Next time he increas
speed by 4 km/h but still he is late by 10 min. Find the distance of the school from his house​

Answer 1

Answer:

1. A boy walking at a speed of 10 km/hr reaches his school 15 minutes late. Next time he increases his speed by 2 km/hr, but still, he is late by 5 minutes. Find the distance of his school from his house.

here is the answer for this question find the same formula to reach on you answer

Let the distance of his school from the house be x

⇒  The difference in time =(15−5)min  

                                           =10 min

                                           =  $\frac{10}{60}$ hr

                                           = $\frac{1}{6}$   hr

⇒  Speed during next journey =10+2=12km/hr

According to the question,

⇒    $\frac{x}{10}$ -$\frac{x}{12}$ =  $\frac{1}{6}$

⇒    $\frac{x}{5}$ - $\frac{x}{6\\}$   =  $\frac{1}{3\\}$  

⇒    $\frac{6x-5x}{30}$ =  $\frac{1}{3}$

⇒   $\frac{x}{30}$      = $\frac{1}{3}$

⇒  x        =   $\frac{30}{3}$

 ∴  x=10km

∴   The distance of boy school from house is 10km

Answer 2

Step-by-step explanation:

time difference=20\60

_speed = S1*S2 \s1-S2

20\60 =20*24\4

ans 40