Question
Pipes X and Y can fill a tank in 48 minutes and 80 minutes
respectively. Another pipe Z can empty the tank in 2 hours. X and Z are opened together. If after 36 minutes, Y is also opened, then how long will it take to fill the tank completely?Solution
ATQ,
Let the capacity of the tank be 240 litres (LCM of 48, 80 and 120)
Efficiency of X = 240 ÷ 48 = 5 litres/minute
Efficiency of Y = 240 ÷ 80 = 3 litres/minute
Efficiency of Z = 240 ÷ 120 = -2 litres/minute (since it is an outlet pipe)
Tank filled in 36 minutes = (5 - 2) × 36 = 108 litres
Remaining tank to be filled = 240 - 108 = 132 litres
Time to fill remaining = 132 ÷ (5 + 3 - 2) = 132 ÷ 6 = 22 minutes
Total time taken = 36 + 22 = 58 minutes
25   25   37.5   ?   328.125   1804.6875
18, 35, 68, 117, ?, 263Â
Find the missing number, in the given number series.
42, 52, 72, 112, 192, ?
Find the missing character.
Find the missing number in the given number series.
512, 128, 32, 8, ?, 116Â Â Â 25Â Â Â 36Â Â Â 49Â Â Â 64Â Â Â Â ?
7 47 ? 223 359 527
...What will come in the place of questions (?) mark in the following questions.
1279, 1265, ? , 1225, 1193, 1149
30, 43, 58, 75, 94, ?
What will come in place of the question mark (?) in the following series?
81, 83, 87, 95, 111, ?