My understanding is:
Using the gradient formula "(T-D)/W x 100", we can see that with the deployment of flaps, the gradient would reduce (due to the drag added). And since Rate of Descent (RoD) = gradient x Ground Speed (GS), the RoD will naturally decrease.
However, when doing questions, it is apparent that the gradient increases rather than the reduction I expected.
Can anyone provide some explanation on it? Am I using the wrong formula or viewing it in the wrong way?