Large, medium and small ships are used to bring water. 4 large ships carry as much water as 7 small ships; 3 medium ships carry as much water as 2 large ships and 1 small ship. If 15 large, 7 medium and 14 small ships, each made 36 journeys to bring a certain quantity of water, then in how many journeys will 12 large, 14 medium and 21 small ships bring the same quantity of water? Pick one:
A) 29 journeys B) 30 C) 20 D) 50 E) 55
Explanation :   Here, Large, Medium and Small ships are denoted by the symbol L, M and S.   Now, according to the question,   4L = 7S. ------(i)   3M = 2L + S. ------(ii)   Using above equations, the ratios of the capacity of the Large, Medium and Small ships are :-   7: 6 : 4.   Let, the number of journeys required be x. Since, quantity of water remains the same, so :-   =((15×7+7×6+ 14×4)36) = x (12×7+14×6+21×4).   =&gt;((15×7+7×6+14×4)36) / (12×7+14×6+21×4)= x   =&gt;x=7308/252   =&gt;x=29.   29 journeysnswer : 29 journeys
<result>A</result>
Large, medium and small ships are used to bring water. 4 large ships carry as much water as 7 small ships; 3 medium ships carry as much water as 2 large ships and 1 small ship. If 15 large, 7 medium and 14 small ships, each made 36 journeys to bring a certain quantity of water, then in how many journeys will 12 large, 14 medium and 21 small ships bring the same quantity of water?