Multiple choice

Two coal loading machines each working x hours per day for 8 days handles 9000 tonnes of coal with an efficiency of 90% while 3 other coal loading machines at an efficiency of 80% set to handle 12000 tonnes of coal in 6 days each working 16 hours per day. Find the value of x. दो कोयला ढोने की मशीन प्रत्येक 90% कार्यक्षमता के साथ 8 दिनों में x घण्टे प्रतिदिन कार्य करके 9000 टन कोयला ढोती है। जबकि 3 दूसरे प्रकार की मशीन 80% कार्यक्षमता के साथ 6 दिनों में 16 घंटे प्रतिदिन कार्य करके 12000 टन कोयला ढोती है। x का मान ज्ञात कीजिए।

  1. 10

  2. 12

  3. 14

  4. 16

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Using the work formula: Work = Machines × Hours per day × Days × Efficiency. For first setup: 2 × x × 8 × 0.9 = 14.4x. For second: 3 × 16 × 6 × 0.8 = 230.4. Since work is proportional to coal handled: 14.4x/9000 = 230.4/12000. Cross-multiplying: 14.4x × 12000 = 9000 × 230.4, which gives 172800x = 2073600, so x = 12 hours per day.