Three pipes P Q and R can fill a tank in 12 15 and 20 minutes respectively If pipe P is opened all t...........

Quantitative Aptitude ( CCS) Pipes&cistern

Three pipes P, Q and R can fill a tank in 12, 15 and 20 minutes respectively. If pipe P is opened all the time and pipe Q and R are opened for one hour alternatively. The tank will be full in ?

5hr

6hr

7hr

8hr

छोटे Courses बड़े Results

Master Pipes&cistern

Prepare through Micro-courses

Try Now

Explanation:

Answer & Explanation
Answer – c) 7hr
Explanation :
(1/12 + 1/15) + (1/12 + 1/20) = 17/60 (in 2 hrs this much tank is filled)
so in 6 hrs 51/60 is filled. Remaining, 9/60 = (1/12 + 1/15)*t, so T = 1hr
so total = 6 + 1 = 7 hr