Dropping Quests in Hearthstone

In Blizzard's Hearthstone, you are given the option of "dropping" a quest one time per day. This will replace it with a "random" quest.

The trouble is, some quests are worth 40 gold, others 60 and one is 100 gold. My question is, if you drop a 60 gold quest, will you always be given another 60 gold quest, or could you end up with a 40 or the 100 gold quest? (I have always been too fearful of losing 20 gold to test this out!)

You can end up with any quest if you reroll, so if you have a 40 gold quest and reroll there is a chance to get a 60 or 100 gold quest. The higher value quests are rarer than the 40 gold quests though in my unscientific, personal observation.

This should also work the other way around, though I haven't checked this myself as I generally don't want to waste the 20 gold. So I would not reroll 60 gold quests unless you have no reasonable deck for the heros in question or simply don't enjoy playing them.