All Exams Test series for 1 year @ ₹349 only
Question

Shweta starts walking from her office and walks 150 m towards the south, then she turns right and walks 80 m, and then she turns left and walks 60 m. She finally turns left and walks 280 m to reach a bank. What is the shortest distance between her office and the bank?

This question was previously asked in
SSC CGL 2020 (Tier-2) Statistics Previous Year Paper 3 (28-Jan-2022)
The correct answer is

290 m 

Calculating Shortest Distance Between Office and Bank

The problem asks us to find the shortest distance between Shweta's starting point (office) and her ending point (bank) after a series of movements. This involves finding the net displacement, which is the straight-line distance from the start to the end point, regardless of the path taken.

Analyzing Shweta's Movements

Let's break down Shweta's walk step by step:

  • Starts at the office.
  • Walks 150 m towards the South.
  • Turns Right (from facing South, Right is West) and walks 80 m.
  • Turns Left (from facing West, Left is South) and walks 60 m.
  • Finally turns Left (from facing South, Left is East) and walks 280 m to reach the bank.

Determining Net Displacement

We can represent the movements in terms of East-West and North-South directions to find the total change in position from the office.

Southward movements:

  • 150 m South
  • 60 m South

Total displacement towards South = $150 \text{ m} + 60 \text{ m} = 210 \text{ m South}$

Eastward/Westward movements:

  • 80 m West
  • 280 m East

Total displacement towards East = $280 \text{ m East} - 80 \text{ m West} = 200 \text{ m East}$ (since East > West)

So, the final position (bank) is 210 m South and 200 m East from the starting position (office).

Using the Pythagorean Theorem

The office, the bank, and a point representing the net displacement towards South and East form a right-angled triangle. The shortest distance between the office and the bank is the hypotenuse of this triangle. We can use the Pythagorean theorem to find this distance.

Let:

  • Net Southward displacement = Perpendicular side = 210 m
  • Net Eastward displacement = Base side = 200 m
  • Shortest distance (Office to Bank) = Hypotenuse = $d$

According to the Pythagorean theorem: $Hypotenuse^2 = Base^2 + Perpendicular^2$

So, $d^2 = (200 \text{ m})^2 + (210 \text{ m})^2$

Calculating the squares:

$d^2 = 40000 + 44100$

$d^2 = 84100$

To find $d$, we take the square root of both sides:

$d = \sqrt{84100}$

$d = 290 \text{ m}$

The shortest distance between Shweta's office and the bank is 290 m.

Summary of Movements and Displacement

Step Direction Distance (m) Net North-South (m) Net East-West (m)
Start (Office) - 0 0 0
1 South 150 -150 (South) 0
2 Right (West) 80 -150 (South) -80 (West)
3 Left (South) 60 -150 + (-60) = -210 (South) -80 (West)
4 Left (East) 280 -210 (South) -80 + 280 = 200 (East)
End (Bank) - - -210 (South) 200 (East)

The net displacement is 210 m South and 200 m East. Using Pythagorean theorem: $\sqrt{(-210)^2 + (200)^2} = \sqrt{44100 + 40000} = \sqrt{84100} = 290$ m.

Final Answer

The shortest distance between her office and the bank is 290 m.

Revision Table: Distance and Displacement

Concept Definition Key Characteristics How it relates to this problem
Distance Total length of the path covered during motion. Scalar quantity, always positive, depends on path. Total distance walked by Shweta is 150+80+60+280 = 570 m. (Not asked in the question)
Displacement Shortest distance between the initial and final positions. Vector quantity (has magnitude and direction), can be zero or negative, independent of path. The shortest distance between office (start) and bank (end) is the magnitude of the displacement vector.

Additional Information: Directions and Turns

Understanding directions and turns is crucial for solving navigation problems like this. Standard directions are North, South, East, West.

  • When facing North, a Right turn is East, a Left turn is West.
  • When facing South, a Right turn is West, a Left turn is East.
  • When facing East, a Right turn is South, a Left turn is North.
  • When facing West, a Right turn is North, a Left turn is South.

In this problem:

  • Starts walking South.
  • Turns Right: Now facing West.
  • Turns Left: Now facing South again.
  • Turns Left: Now facing East.

This detailed breakdown of movements helps confirm the directional components used in the displacement calculation.

Was this answer helpful?

Important Questions from Direction and Distance Turns

  1. After leaving school, Hemant and Anurag walk towards the north for 1 km to reach a bus stop. From the bus stop, Hemant turns left and walks for 500 m. Then he turns towards his left and walks for 2 km to reach his home. From the bus stop, Anurag turns right and walks for 250 m. Then he turns right and walks for 1 km to reach his home. In which direction is Anurag's home from Hemant's home?

  2. A bank employee drives 10 km towards South from her house and turns to her left and drives another 20 km. She again turns left and drives 40 km, then she turns to her right and drives for another 5 km. She again turns to her right and drives another 30 km to reach her bank where she works. What is the shortest distance between her bank and her house ?

  3. A woman runs 12 km towards her North, then 6 km towards her South and then 8 km towards her East. In which direction is she from her starting point ?

  4. Two friends Xand Ystart running and they run together for 50 m in the same direction and reach a point. Xturns right and runs 60 m, while Yturns left and runs 40 m. Then Xturns left and runs 50 m and stops, while Yturns right and runs 50 m and then stops. How far are the two friends from each other now?

  5. Shekhar starts walking south from his school and then took one right turn, one left turn and one right turn to reach his shop. In which direction is Shekhar with respect to his school?

Need Expert Advice?
Upcoming Exams
SSC CGL
September 30, 2026
UPSSSC PET
October 23, 2026
Test Series
SSC CGL img
SSC
SSC CGL (Tier I + Tier II) 2026 Mock Test Series - Latest Pattern
2503 Tests 6 Tests Free
5389 Attempts
4.2(868)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App