Question

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 the same amount of water as 2 large ships, and 1 small ship. 15 large, 7 medium and 14 small ships each made 36 journeys and brought a certain quantity of water. In how many journeys would 12 large, 14 medium and 21 small ships bring the same quantity ?

• A. 32
• B. 25
• C. 29
• D. 49

Answer 1

Answer: (C)

29

Answer 2

Let's take the large ships be l, the medium one's be m and small one's be s.
From the information given in the question, we get that
4l = 7s
3m = 2l + 1s
6m = 4l + 2s, so 6m = 9s, so 2m = 3s, m = $\frac{3s}{2}$ = $\frac{6l}{7}$
Total quantity of water in 36 journeys:
t = 36 × [15l + 7m + 14s] = 36 × [15l+6l+8l] = 36 × 29l
t = x [12l+14m+21s], here x = number of journeys
36 × 29l = x[12l + 12l + 12l] = 36l × x
x = 29
So, The total journey will be 29

The correct option is (C)