Rafiq exercised = 36\frac{3}{6}63 of an hour.
Rohit exercised = 34\frac{3}{4}43 of an hour.
On comparing fractions 36\frac{3}{6}63 and 34\frac{3}{4}43 we get 34\frac{3}{4}43 >>> 36\frac{3}{6}63
With equal numerators, the fraction with the smaller denominator gets the bigger slice of the pie..
Hence, Rohit exercised for a longer time.