Today, Samson’s Train traveled at a constant rate along a st

Notice that we are told that the train traveled at a constant rate.

Furthermore for option # 2 , not clear on what is meant by "less than". Does it mean the speed could be anything less than 70mph ?

Yes, it means exactly that.

Hi

So because it is mentioned that the train traveled at a constant speed the average speed becomes the actual speed of the train ?

Regards
Sandy Da Silva

Statement 1;
Between 9am and 4pm -- a total of 7 hours -- the total distance traveled by the train = (200 north of the bridge) + (10-mile bridge) + (140 miles south of the bridge) = 200+10+140 = 350 miles.
Since 350 miles are traveled in 7 hours, the train's rate = d/t = 350/7 = 50 mph.
Distance traveled in the 5 hours between 9am and 2pm = rt = 50*5 = 250 miles.
Since the 250 miles traveled by 2pm is 40 miles greater than the 210-mile blue distance above, the train at 2pm must be 40 miles south of the bridge.
Thus, the answer to the question stem is NO.
SUFFICIENT.

Statement 2:
No information about the distance between the 6am starting point and the location of the bridge.
INSUFFICIENT.

(1) This statement tells us that Samson's train traveled 350 miles between 9 am and 4pm.

350 / 7 = 50 miles per hour
We know at 2 pm Samson's train will have traveled 250 miles; thus, the train was not at Chasm Bridge at 2pm. Sufficient.

(2) Samson's train could have traveled 1 mile per hour or 69 miles per hour. Insufficient.

For me, main points to learn here are below.

When Q said, 200 miles north of C bridge means 200 miles from north end of the bridge. This distance doesn't include the length of bridge.
Similarly, 140 miles south of C bridge means 140 miles from south end of the bridge. Even this distance doesn't include the length of bridge.

Length of bridge is 10 miles.

Question is asking whether train was at C bridge means train engine was at south end of bridge if we consider that train is moving north to south direction.

Considering all above now come to
St. 1 In 7 hours train travelled total 350 miles. means 50miles per hours. Between 9 am to 2 pm- in 5 hours train travelled 250 miles which is more than 200+10 miles. Therefore, train had crossed the bridge at 2:00pm.
Sufficient

St -2 Speed is less than 70 miles/hr.
Speed can be 0.5 mph to 69.9 mph. Moreover, we don't know from where starts.
Insufficient.

A is winner.

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