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

### Instruction:
 一袋开心果里有80颗开心果。其中95%有壳，其中75%的开心果壳是开着的。这袋开心果中有多少颗既有壳又开着壳？


### Response:
 有壳的开心果的比例是95/100 = <<95/100=0.95>>0.95
壳是开着的开心果的比例是75/100 = <<75/100=0.75>>0.75
有壳且壳是开着的开心果的比例是0.95*0.75 = <<0.95*0.75=0.7125>>0.7125
有壳且壳是开着的开心果的数量是0.7125*80 = <<0.7125*80=57>>57