A train running at the speed of 30 km/hr crosses a pole in 9 sec. What is the length of the train?
Options:
(A) 75 m
(B) 180 m
(C) 324 m
(D) Cannot be determined
(E) None of these

Speed = 30 * 5/18 = 25/3 m/sec
Length of the train = speed * time = 25/3 * 9 = 75 m So the answer is: (A).

A person spends 1/3rd of the money with him on clothes, 1/5th of the remaining on food and 1/4th of the remaining on travel. Now, he is left with Rs 300. How much did he have with him in the beginning?
Options:
(A) s 200
(B) s 750
(C) s 300
(D) s 450
(E) s 550

Suppose the amount in the beginning was Rs 'x'
Money spent on clothes = Rs 1x/3 Balance = Rs 2x/3
Money spent on food = 1/5 of 2x/3 = Rs 2x/15
Balance = 2x/3 - 2x/15 = Rs 8x/15
Money spent on travel = 1/4 of 8x/15 = Rs 2x/15 = 8x/15 - 2x/15 = 6x/15 = Rs2x/5
Therefore 2x/5 = 300 = 750 So the answer is: (B).

A class consists of 100 students, 25 of them are girls and 75 boys; 20 of them are rich and remaining poor; 20 of them are fair complexioned. The probability of selecting a fair complexioned rich girl is
Options:
(A) 1/125
(B) 1/59
(C) 1/56
(D) 1/54
(E) 1/53

The probability of selecting girl is: 25/100 = 1/4
The probability of selecting rich is: 20/100 = 1/5
The probability of selecting fair complexioned is: 20/100 = 1/5
Three are independent;probability of rich and fair complexioned girl is:
(1/4) (1/5) (1/5) = 1/125 So the answer is: (A).

Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is?
Options:
(A) 60 gallons
(B) 100 gallons
(C) 120 gallons
(D) 180 gallons
(E) 130 gallons
Work done by the waste pipe in 1 minute = 1/15 - (1/20 + 1/24) = - 1/40
Volume of 1/40 part = 3 gallonsVolume of whole = 3 * 40 = 120 gallons. So the answer is: (C).