At a cinema hall for a matinee show from 2.30 pm to 5.30 pm, the parking lot contains only three wheelers (auto rickshaws) and four wheelers (cars). The total number of wheels counted in the parking area is 240. How many three wheelers are parked there?

Introduction / Context:
This is a classic puzzle involving a mixture of two types of vehicles with different numbers of wheels. You are given only the total number of wheels and must find how many three wheelers are present, using the fact that the rest are four wheelers.

Given Data / Assumptions:
- The parking lot has only three wheelers and four wheelers.
- Each three wheeler has 3 wheels and each four wheeler has 4 wheels.
- The total number of wheels is 240.
- We need to find the number of three wheelers from among the options.

Concept / Approach:
Let the number of three wheelers be t and the number of four wheelers be f. The total wheels equation is 3t + 4f = 240. With only this equation there are infinitely many pairs (t, f) in theory, but the options restrict t to specific values. So we can test each option by substituting its value for t and checking whether f comes out as a non negative integer.

Step-by-Step Solution:
Step 1: Let t be the number of three wheelers. Then the total number of wheels is 3t + 4f = 240. Step 2: Rearrange to find f in terms of t: 4f = 240 - 3t, so f = (240 - 3t) / 4. Step 3: Try option t = 48. Then f = (240 - 3 * 48) / 4 = (240 - 144) / 4 = 96 / 4 = 24. Step 4: For t = 48, f is a whole number (24), so this is a valid solution. Step 5: We check other options to verify that they do not give integer values of f.

Verification / Alternative check:
With t = 48 three wheelers and f = 24 four wheelers, the total wheels are 48 * 3 + 24 * 4 = 144 + 96 = 240, which matches the given total. Therefore, this pair of values is consistent with the problem statement.

Why Other Options Are Wrong:
- Option 41: f = (240 - 3 * 41) / 4 = (240 - 123) / 4 = 117 / 4, which is not an integer.
- Option 45: f = (240 - 3 * 45) / 4 = (240 - 135) / 4 = 105 / 4, again not an integer.
- Option 43: f = (240 - 3 * 43) / 4 = (240 - 129) / 4 = 111 / 4, also not an integer.

Common Pitfalls:
Some learners try to guess by proportion or by approximate reasoning without using the equation. Others forget that the number of vehicles must be a whole number and accept a fractional value for f. Always set up the equation correctly and insist on integer solutions when counting real objects like vehicles.

Final Answer:
The number of three wheelers parked in the lot is 48.