Q: How much weight would I want to aim to lose in order to drop say 2 pant sizes? I'm not sure if it's relevant but I am a tall and slender female. I wear size 7/8 in pants and want to fit into size 5/6 or maybe a little smaller.

A: I'm guessing it's about 2-3 inches difference which corresponds to maybe around 15 pounds.

You should also keep in mind that it's possible, with a good diet and a good workout program, to lose a couple of inches with only minimal weight loss. So I'd rather put it in terms of months and say it may take 3-4 months to do this right. 'Right' means making sure your muscle mass and metabolism stay normal and guard against all that fat coming back. It's certainly possible to go on a crash diet and lose 15 pounds within a month, but it's pretty much guaranteed to come back quickly afterwards. Slow and steady wins the race here.