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Territorial Army Paper I : Official Practice Test Paper - 2

Option 3 : \(3\dfrac{3}{7}\) days

**Given**

A, B and C can complete a piece of work in 24, 6 and 12 days respectively.

**Concept used**

Total work = Number of days × efficiency

**Calculation**

Total work : Lcm of (24, 6 and 12)

Total work = 24 unit

Efficiency of A = 24/24 = 1 unit

Efficiency of B = 24/6 = 4 unit

Efficiency of C = 24/12 = 2 unit

Together they do work in

⇒ \(\frac{{24}}{{1 + 4 + 2}}\)

∴ \(3\dfrac{3}{7}\) days.