AMC 8 1992 Problem 25

One half of the water is poured out of a full container. Then one third of the remainder is poured out. Continue the process: one fourth of the remainder for the third pouring, one fifth of the remainder for the fourth pouring, etc. After how many pourings does exactly one tenth of the original water remain? $\text{(A)}\ 6 \text{(B)}\ 7 \text{(C)}\ 8 \text{(D)}\ 9 \text{(E)}\ 10$