Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
Iris has a berry farm. Her brother and sister help her to pick up the berries and sell them to the market. Iris picked 30 blueberries, her sister picked 20 cranberries, and her brother was able to pick 10 raspberries. If 1/3 of the total berries they were able to pick are rotten and the remaining 1/2 of the fresh berries need to be kept, how many berries will they be able to sell?

### Response:
The total number of berries they were able to pick is 30 + 20 + 10 = <<30+20+10=60>>60.
One-third (1/3) of the total berries are rotten, so they are 60 x 1/3 = <<60*1/3=20>>20.
So, the total number of fresh berries is 60 - 20 = <<60-20=40>>40.
One-half (1/2) of the fresh berries need to be kept, so they are 40 x 1/2 = <<40*1/2=20>>20.
Therefore, the total number of berries they will be able to sell is 40 - 20 = <<40-20=20>>20.
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