A girl walks 500m towards East and then 1.2 km towards North. The dist...
Distance of a girl from the starting point
Given, a girl walks 500m towards East and then 1.2 km towards North. We need to find the distance of the girl from the starting point.
Concept:
Distance is the total length of the path covered by an object. In this question, the girl has walked in two different directions, so we need to use Pythagoras theorem to calculate the distance of the girl from the starting point.
Pythagoras theorem:
According to Pythagoras theorem, in a right-angled triangle, the square of the hypotenuse (the longest side) is equal to the sum of the squares of the other two sides.
Mathematically, if a and b are the lengths of the legs (the two shorter sides) of a right-angled triangle and c is the length of the hypotenuse, then:
c² = a² + b²
Solution:
Let's assume that the starting point is O, and the girl walks 500m towards East and reaches point A. From point A, she walks 1.2 km towards North and reaches point B.
Using Pythagoras theorem, we can find the distance of the girl from the starting point:
Distance OB = √(OA² + AB²)
OA = 500m (as she walks 500m towards East)
AB = 1.2 km = 1200m (as she walks 1.2 km towards North)
Distance OB = √(500² + 1200²)
Distance OB = √(250000 + 1440000)
Distance OB = √(1690000)
Distance OB = 1300m
Therefore, the distance of the girl from the starting point is 1300m.