If a car had traveled 35 kmh faster than it actually did, the trip would have lasted 30 minutes less. If the car went exactly 105 km, at what speed did it travel? Choose one.
A) 50 kmh
B) 55 kmh
C) 60 kmh
D) 65 kmh
E) 70 kmh

Rationale: "time = distance / speed difference in time = 1 / 2 hrs 105 / x - 105 / ( x + 35 ) = 1 / 2 substitute the value of x from the options . - - > x = 70 - - > 105 / 70 - 105 / 105 = 3 / 2 - 1 = 1 / 2 answer : e"
Answer: E