Question

ritu walks to her school at a speed of 4 km per hour and takes 45 minutes to reach
the school in time. One day she reached the school 10 minutes late. At what speed
she walk that day, assuming that she did not start late from home​

Answer 1

I am confused in two different processes same answers, so I am giving both processes-

1st Process

Walking Speed 4 Km/per hour x Time takes 45 minutes 55 minutes

Walking Speed 4 Km/per hour x Time takes 45 minutes 55 minutesThis is inverse proportion

Walking Speed 4 Km/per hour x Time takes 45 minutes 55 minutesThis is inverse proportion so

Walking Speed 4 Km/per hour x Time takes 45 minutes 55 minutesThis is inverse proportion so4 x 45 = 55x

Walking Speed 4 Km/per hour x Time takes 45 minutes 55 minutesThis is inverse proportion so4 x 45 = 55x180 = 55x

x = 180/55

x = 180/55x = 3.27

Hence, she walked at the speed of 3.27 km/per hour.

2nd Process

x1y1 = x2y2

x1y1 = x2y24 * 45 = x * 55 (45 + 10)

x1y1 = x2y24 * 45 = x * 55 (45 + 10)x = 4 * 45 / 55

So, she walked at the speed of around 3.27 km/hour.

Answer 2

Question :-

Ritu walks to her school at a speed of 4 km per hour and takes 45 minutes to reach the school in time. One day she reached the school 10 minutes late. At what speed she walk that day, assuming that she did not start late from home.

Answer :-

Given:

• Speed of Ritu while going to school = 4 km/hr.
• Time taken by Ritu to reach school at 4 km/hr speed = 45minutes

To find:

• Speed of Ritu when she was 10 minutes to reach the school

Understanding the Question:

• Ritu always walks at a speed of 4 km/hr and reaches the school with the time interval of 45 minutes.
• We have to find the her speed when she reached the school 10 minutes late.
• For that, we have to find the distance from her home to school.

Required Formula:

• Speed =$\frac{Distance}{Time}$

Solution:

(We know that 45 minutes = 0.75 hours)

$Speed=\frac{Distance}{Time}\\=Distance=Speed\times{Time}\\=Distance=4\times0.75\\=Distance=3\:km/hr$

(If Ritu reached school 10 minutes late, time becomes 55 minutes = 0.916 hours)

$Speed\:after\:reaching\:10\:minutes\:late\\=\frac{3}{0.916}\\=3.27\:km/hr$