Giải:
Nếu lừa chuyển cho ngựa một bao thì lừa và ngựa chở bằng nhau, vậy lừa chở nhiều hơn ngựa:
1+1=2 (bao)
Nếu ngựa chuyển cho lừa một bao thì lừa sẽ chở hơn ngựa 2 bao nữa, khi đó lừa chở nhiều hơn ngựa:
2+2=4 (bao)
Khi đó ngựa chở: 4 bao
Lừa chở: 4.2 = 8 (bao)
Ban đầu ngựa chở: 4+1 = 5 (bao)
Ban đầu lừa chở: 8-1 = 7 (bao)
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