Statement 1: Alone is insufficient as distance is unavailable.

Statement 2: Alone is insufficient as neither speed nor distance is available.

Combining Both: From Statement 1 we know that 72 km/hr is the avg. speed. Let the time taken by helen be X.

Thereforhome.e distance travelled by Helen is 72*X

From statement 2, we know that if the speed had been 8 km/hr more than the original it would take 1 hr less.

=> 72X/80 = X-1

Therefore we can solve for X, which is the time take by Helen.

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'It's not the ride, it's the rider'