How to add time in Date which is selected in DateTimePicker?

Question

I am Creating Date & Time Calculator in vb.net. I want to add Hours, Minute, Second in Date which is selected in datetimepicker1 and time which is in in other datetimepicket2. How to add time?

For Example,

Selected Date: 13-Mar-14 (Datetimepicker1)
Selected Time: 9:15:00 AM (Datetimepicker2)

Now I want to add "24 Hours 30 Minute 00 Seconds"(Textbox1, Textbox2, Textbox3)

My Answer Will be "14-Mar-14 9:45:00"

How can I do it? Help me...