City Guilds Model Questions Vol1 2024 Engineering Question 22

A workshop floor measures 120 m\(^2\) with a ceiling height of 3 m. The space stores wood, oil and electrical equipment. Safety code requires fire‑extinguishers as follows: Class A (wood) - 2 L per 30 m\(^2\); Class B (oil) - 1 L per 30 m\(^2\); Class C (electrical) - 1 L per 30 m\(^2\). Extinguishers are available in the sizes: 2 L Class A (cost ₦12 000 each), 1 L Class B (cost ₦8 000 each), 1 L Class C (cost ₦9 000 each). The total number of extinguishers may not exceed 10 because of space limits.\n\nDetermine the minimum numbers of each dedicated extinguisher type required and the total cost. If the 10‑extinguisher limit is exceeded, suggest an alternative using multi‑class 2 L extinguishers (cost ₦15 000 each, each covering all three classes) that satisfies the safety requirements with the lowest possible cost. State the final numbers of each extinguisher type and the total expense.