Question

Two friends a and b start walking from a common point. a goes 20 kms towards north-east whereas b goes 16 kms towards east and then 12 kms towards north. how far are a and b from each other ?

Answer 1

Answer:

a and b are present together at one point and there is zero km between them.

Step-by-step explanation:

This can be derived as follows-

If we track the movement of 'a' at first, he goes towards east and then towards north, thereby forming a right angle.

The hypotenuse of this triangle if measured comes to 20km.

Since, b also goes towards north east from the same starting point, it can be stated that a and b meet at the same point.

Answer 2

Answer:

The distance between a and b will be 0 km.

Solution:

To find out the distance between a and b, let us refer to the diagram given below, where a and b start from the same point P.

Thus, Displacement of a = Distance travelled by a = 20 km.

[According to Pythagoras Theorem]

Displacement of b  

$\begin{aligned} = & \sqrt { ( 16 k m ) ^ { 2 } + ( 12 k m ) ^ { 2 } } \\\\ = & \sqrt { 256 \mathrm { km } ^ { 2 } + 144 \mathrm { km } ^ { 2 } } \\\\ & = \sqrt { 400 \mathrm { km } ^ { 2 } } \\\\ & = 20 \mathrm { km } \end{aligned}$

Thus, it can be seen that Displacement of a = Displacement of b = 20 km.

So a and b will again meet each other at the end point of their journey.

Therefore, the distance between them will be = 20 km – 20 km = 0 km.