The following question has two statements. Study the question and the statements and decide which of the statement(s) is necessary to answer the question. Train A leaves New York for Boston at 2 PM and travels at the constant speed of 100 mph. An hour later, it passes Train B, which is making the trip from Boston to New York at a constant speed. If Train B left Boston at 2:50 PM and if the combined travel time of the two trains is 2 hours, what time did Train B arrive in New York? I) Train B arrived in New York before Train A arrived in Boston. II) The distance between New York and Boston is greater than 140 miles.

The following question has two statements. Study the question and the statements and decide which of the statement(s) is necessary to answer the question. Train A leaves New York for Boston at 2 PM and travels at the constant speed of 100 mph. An hour later, it passes Train B, which is making the trip from Boston to New York at a constant speed. If Train B left Boston at 2:50 PM and if the combined travel time of the two trains is 2 hours, what time did Train B arrive in New York? I) Train B arrived in New York before Train A arrived in Boston. II) The distance between New York and Boston is greater than 140 miles. Correct Answer Either I or II

Let ‘d’ miles be the distance between cities and ‘x’ mph be the speed of train B

Speed of train A = 100 mph

Combined travel time of the two trains is 2 hours

⇒ d/100 + d/x = 2    ----(1)

An hour later (so at 3:00 PM), Train A passes Train B,

Distance travelled by A in 1 hour (3 PM - 2 PM) = 1 × 100 = 100 miles

Distance travelled by B in 1/6 hours (3 PM - 2:50 PM) = 1/6 × x = x/6 miles

⇒ Total distance between cities = 100 + x/6 = d    ----(2)

Substituting (2) in (1), we get,

⇒ (100 + x/6)(1/100 + 1/x) = 2

⇒ 1 + x/600 + 100/x + 1/6 = 2

⇒ x/600 + 100/x = 5/6

⇒ x2 - 500x + 60000 = 0

⇒ x = 200, 300

Substituting in (2),

⇒ d = 133.3, 150

If x = 200 mph, train A arrives at 3:20, train B at 3:30

If x = 300 mph, train A arrives at 3:30, train B at 3:20

Considering statement I,

Train B reached its destination before train A, hence, arrival time of train B is 3:20 PM

Considering statement II,

⇒ d > 140

⇒ d = 150 miles

Hence, arrival time of train B is 3:20 PM

∴ The question can be answered using either of the statements

Related Questions

Each of the question below consists of a question and three statements number I, II and III given below it. You have to decide whether the data provided in the statement are sufficient to answer the question. If the bus is travelling from Surat to Ahmadabad and a car is travelling from Ahmadabad to Surat, then what is the distance between Surat and Ahmadabad? I. The speed of a car is 40% less than the speed of bus. Bus started at 9 am and car started at 10 am and they meet at 3 pm of the same day. II. After travelling for 1 hour, because of traffic average speed of bus is decreased by 20% and covers distance between Surat to Ahmadabad in 11 hours. Original speed of car is 20% less than original speed of bus and before crossing bus it covered 200 km if starts 1 hour later than bus. After crossing car, bus covers remaining distance in 5 hours. III. Speed of bus is 10 km/hr more than the speed of car and before crossing car ratio of distances covered bus and car in same time was 5 : 4. Time taken by car to cover the distance between Ahmadabad and Surat is 2 hours 15 minutes more than time taken by bus to cover the same distance.
The question below is followed by two statements I and II. You have to determine whether the data given is sufficient for answering the question. You should use the data and your knowledge of mathematics to choose the best possible answer. Train A departs at 9 : 20 am and train B departs at 10 : 50 am and they travel towards each other. After how much amount of time will the trains meet? I) Train A travels with a speed of 10 kmph and the difference between the speed of two trains is 6 kmph and both the trains are 160 km apart. II) Train B travels at a speed greater than Train A which travels with 10 kmph by 6kmph separated by a distance of 160 km.