'Grapes' is plural and countable, so we must use 'How many'. Have a wonderful day, too! :)

The trick to this question is that many people will use much for everything. It's pretty common, in speech particularly. Best not to correct them. Best to just use the correct word yourself.

countable. If you can put a number before it , then many. . How much sugar? Only a little. How many grapes? eg 4 How many cups of sugar. eg 3 How much water? Lots. How many cups of water? eg 5

Hi Katya! It should be "How many" because you can count the grapes (countable noun).