Pipe A can fill a tank in 16 hours, pipe B can fill the same tank in 28 hours and pipe C can fill the same tank in 8 hours. The time taken by them to fill the same tank if they operate together is:

Correct option is A

Given:

Pipe A fills in 16 hours

Pipe B fills in 28 hours

Pipe C fills in 8 hours

Formula Used:

Time = Total work ÷ Total rate

Solution:

LCM of 16, 28, and 8 = 112 units (assumed tank capacity)

Work per hour:

A = $$\frac{112} {16}$$​ = 7 units

B = $$\frac{112} {28}$$​ = 4 units

C = $$\frac{112} 8$$​ = 14 units

Total work per hour = 7 + 4 + 14 = 25 units

Time taken together = $$\frac{112} { 25}$$​ = $$4\frac{12}{25}$$​ hours