A four pound duck, initially at a temperature of 50 degrees is place in an oven preheated to 375 degrees at 1:00. At 2:15 the duck has reached an internal temperature of 125 degrees. When will it reach 175 degrees.

1:00 to 2:15 is 1 hour and 15 minutes.

In that time the duck went from 50 to 125, which is a 75 degree increase.

75 degrees / 75 minutes = 1 degree per minute increase.

175 degrees - 125 degrees = 50 degree more it needs.

1 degree per minute x 50 degrees = 50 more minutes.

50 minutes after 2:15, would be 3:05

It will be 175 degrees at 3:05