There is a numeric lock which has a 3-digit PIN. The PIN contains digits 1 to 7. There is no repetition of digits. The digits in the PIN from left to right are in decreasing order. Any two digits in the PIN differ by at least 2. How many maximum attempts does one need to find out the PIN with certainty?
The correct answer is D
Pipe M and N can fill a tank together in 25 hours while pipe N alone can fill the tank in 30 hours. Find the time taken by pipe M to fill the tank if it...
There was the leakage in the Oil tanker. If 20 litre of oil is leaked out per day then it would have lasted for 50 days and if the leakage was 32 litre ...
Pipes ‘A’ and ‘B’ can fill a tank in 6 hours and 9 hours, respectively. If pipe ‘C’ is opened along with pipes ‘A’ and ‘B’, then the...
In what time would a cistern be filled by three pipes whose diameter are 2cm, 2*2/3cm, 4cm running together, when the largest pipe alone fill the cister...
Pipe ‘A’ can fill a tank in 25 hours while pipe ‘B’ can empty it in 30 hours. They were operated on alternate hours starting with pipe ‘A’. ...
A water tank has two holes. The 1 hole alone empties the tank in 9 minutes and 2nd hole alone empties the tank in 6 minutes. If water leaks out at a con...
P, Q and R three pipes connected to a tank. P and Q together fill the tank in 30 hours, Q and R together fill the tank in 40 hours. P and R together fil...
Pipe ‘A’ can fill a 120-litre tank in 15 hours. If pipe ‘A’ is 25% more efficient than pipe ‘C’ whereas pipe ‘B’ is 50% more efficient t...
Two inlet pipes M and N alone can fill a tank in 12 hours and 15 hours respectively and an outlet pipe P alone can empty the whole tank in 10 hours. Fir...
Pipe ‘A’ can fill a 180-litre tank in 18 hours. If pipe ‘A’ is 25% more efficient than pipe ‘C’ whereas pipe ‘B’ is 50% more efficient t...
