A can do a piece of work in 4 hours, B and C together can do it in 3 hours, while A and C together can do it in 2 hours. How long will B alone take to do it?

🧠 Explanation (Math):

Given: A alone 4 h; (B+C) 3 h; (A+C) 2 h; find B alone
Step 1: Rates: A = 1/4, B+C = 1/3, A+C = 1/2 (work/hour)
Step 2: C = (A+C) − A = 1/2 − 1/4 = 1/4
Step 3: B = (B+C) − C = 1/3 − 1/4 = 1/12
Step 4: Time for B alone = 1 ÷ (1/12) = 12 hours
Final Answer: 12