The speed of the Duronto Express is greater than the speed of the Rajdhani Express. The Shatabdi Express moves faster than the Garib Rath Express but slower than the Rajdhani Express. Based on these comparisons of train speeds, which one of the four trains is the slowest?

Introduction / Context:
This verbal reasoning problem involves comparing relative speeds of four trains. Instead of giving exact numerical speeds, the question presents inequality relations such as faster than and slower than. The goal is to use these comparisons to determine which train is the slowest overall. Questions of this type test your ability to translate verbal relations into a logical order and to reason about extremal values like the fastest or the slowest.

Given Data / Assumptions:
- Trains: Duronto, Rajdhani, Shatabdi and Garib Rath. - The speed of Duronto is more than the speed of Rajdhani. - The Shatabdi moves faster than Garib Rath. - The Shatabdi moves slower than Rajdhani. - All trains are considered on the same route or under comparable conditions. - We must identify the train with the lowest speed among the four.

Concept / Approach:
The idea is to express speed comparisons using inequalities. Let higher speed mean greater in an ordering. From the statements, Duronto is faster than Rajdhani, so Duronto is above Rajdhani in the speed order. Shatabdi is slower than Rajdhani but faster than Garib Rath, which gives a chain involving three trains. By combining both pieces of information into a single consistent order, we can see clearly which train lies at the lowest position. No exact speed values are needed; only relative ordering matters.

Step-by-Step Solution:
Step 1: From the statement that Duronto is faster than Rajdhani, write Duronto > Rajdhani in terms of speed. Step 2: From the second statement, Shatabdi moves faster than Garib Rath but slower than Rajdhani. This means Rajdhani > Shatabdi > Garib Rath. Step 3: Combine the inequalities from both steps. We already know Duronto > Rajdhani, and now we have Rajdhani > Shatabdi > Garib Rath. Step 4: The single chain of speeds from highest to lowest is: Duronto, then Rajdhani, then Shatabdi, then Garib Rath. Step 5: The train at the bottom of this chain, with the lowest speed, is Garib Rath.

Verification / Alternative check:
To verify, imagine assigning sample speeds consistent with the inequalities. For example, let Garib Rath have speed 80 units, Shatabdi 90 units, Rajdhani 100 units and Duronto 110 units. These assumed values satisfy all conditions: Shatabdi (90) is faster than Garib Rath (80) and slower than Rajdhani (100), and Duronto (110) is faster than Rajdhani (100). In this example, Garib Rath clearly remains the slowest, confirming the conclusion. Any other set of values that respects the inequalities will also place Garib Rath at the lowest position.

Why Other Options Are Wrong:
- Shatabdi cannot be the slowest because it is explicitly said to be faster than Garib Rath. - Rajdhani cannot be the slowest because Shatabdi is slower than Rajdhani but still faster than Garib Rath. - Duronto cannot be the slowest because it is faster than Rajdhani, which itself is faster than Shatabdi and Garib Rath. - Therefore, only Garib Rath consistently appears at the minimum speed.

Common Pitfalls:
A common error is to misread phrases like slower than and faster than, especially when two comparisons are combined in one sentence. Students may also prematurely assume that Rajdhani or Shatabdi is the slowest without building the full chain of inequalities. Another pitfall is to overlook the impact of the first statement about Duronto and Rajdhani, even though it does not directly mention Garib Rath. Systematically writing a single ordered sequence of speeds avoids these mistakes.

Final Answer:
The train with the lowest speed among the four is Garib Rath.