Suppose you get enough water to dissolve 10 grams in 15 minutes (I assume you're talking about dissolving in water). Then you can dissolve another 10 grams by fetching an equal volume of water and doing the same, also in 15 minutes. Keep doing this. You'll never run out of water. So I suppose the answer is "as many grams of salt as you can find". Or, reading the question differently, the answer could be "as many grams of salt you can find in 15 minutes."
Movies in Fifteen Minutes has 416 pages.
15 grams = 0.53 ounces.
15 ounces = 425.2 grams.
15000
15,000 milligrams
7 hours and fifteen minutes.
You would have eaten 15 grams of pie.
8 fifteen minutes are in two hours
8 fifteen minutes are in two hours
Between ten past nine in the morning and fifteen minutes later - (that is twenty five past nine in the morning), there are zero hours and fifteen minutes.
An hour is sixty minutes. A quarter hour is fifteen minutes.
Fifteen.