Rashmi has a road map with a scale of 1 cm representing 18 km. She drives on a road for 72 km. What would be her distance covered in the map?

Solution:

The map is a representation of a very large region. The scale shows the representation of the actual length and the length represented in the map.

Let the distance in the map be x and the actual distance be y.

1 cm on the map represents 18 km of the actual distance then 2 cm on the map represents 36 km. Hence the scale is based on the concept of direct proportion.

Two numbers x and y are said in direct proportion if, the relationship between two quantities is such that if we increase one, the other will also increase, and if we decrease one the other quantity will also decrease.

x/y = k, x = ky

where k is a constant.

Thus, x₁ / y₁ = x₂ / y₂

1/18 = x₂/72

18 × x₂ = 72 × 1

x₂ = 72/18

x₂ = 4

Thus, her distance covered in the map will be 4 cm.

☛ Check: NCERT Solutions for Class 8 Maths Chapter 13

Video Solution:

Rashmi has a road map with a scale of 1 cm representing 18 km. She drives on a road for 72 km. What would be her distance covered in the map?

NCERT Solutions Class 8 Maths Chapter 13 Exercise 13.1 Question 8

Summary:

Rashmi has a road map with a scale of 1 cm representing 18 km. If she drives on a road for 72 km, her distance covered in the map will be 4 cm.

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