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

### Instruction:
 罗德尼、罗杰和罗恩一共能举起239磅的重量。罗德尼能举起的重量是罗杰的两倍，而罗杰能举起的重量比罗恩的4倍少7磅。罗德尼能举起多少磅？


### Response:
 让x代表罗恩能举起的重量。
罗杰:4x-7
罗德尼:2(4x-7)=8x-14
总共:x+4x-7+8x-14=239
13x-21=239
13x=260
x=<<20=20>>20
罗德尼:8(20)-14=146磅