Hello Taiwo
Alessandro almost explained the concept of delay.I just want to add that you should be familiar to the fiber parameters for exact calculation.One important oint i want to add is delay also depends upon your wavelength.For examples for a specific fiber (for which i have calculated) gives me results 49.16nm for 1310nm and 49.21ns for 1550.So if you are looking for exact delay then consider this point also.Thank you