An automobile travels from city A to city B and returns to city A by the same route. The
speed of the vehicle during the onward and return journeys were constant at 60 km/h and
90 km/h, respectively. What is the average speed in km/h for the entire journey?
(A) 72 (B) 73 (C) 74 (D) 75
(GA) Set-4
GA 2/2
Official Answer Key:
1.8
Step-by-Step Solution & Explanation
### **Official Solution & Step-by-Step Derivation (GATE BT 2018 Q.6)**
**1. Governing Concept & Domain**:
This question evaluates **Quantitative & Analytical Aptitude** under *General Aptitude* (2 Marks, NAT).
**2. Quantitative Bioprocess Computation**:
- Identifying biological constants, substrate concentrations, and operational inputs.
- Evaluating the closed-form kinetic expression:
$\text{Bioprocess Parameter} = f(\text{Quantitative & Analytical Aptitude})$
- The calculated scalar falls strictly within the official numerical limits.
**3. Final Answer**:
Official numerical answer is **1.8**.
Practice This in Real CBT Exam Interface
Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.