A concrete mixer has a drum capacity of 0.3 cubic meters and the mixing time per batch is 5 minutes. If the mixer operates for 8 hours a day with an efficiency of 90%, then how much concrete can it produce in a day?
- A25.92 m³Correct
- B30.24 m³
- C34.56 m³
- D38.88 m³
Solution
Concept
Daily mixer output
Formula
Output = capacity × batches × efficiency
Step-by-step solution
1. Batches per hour = 60/5 = 12; per day = 96. 2. Concrete = 96 × 0.3 = 28.8 m³. 3. With 90% efficiency = 25.92 m³.
Explanation
Efficiency accounts for idle time.
Why the other options are wrong
The other values neglect efficiency or use wrong batch counts.
Shortcut
0.3 × 12 × 8 × 0.9.
Correct answer: A) 25.92 m³