If n is an integer between 0 and 100, then any of the following could be 3n+3 EXCEPT ？（）

A child withdraws from his piggy bank 10% of the origin...

单项选择题A child withdraws from his piggy bank 10% of the original sum in the bank. If he must add 90￠ to bring the amount in the bank back up to the original sum, what was the original sum in the bank ？（）

Last year, an appliance store sold an average (arithmet...

单项选择题Last year, an appliance store sold an average (arithmetic mean) of 42 microwave ovens per month. In the first 10 months of this year, the store has sold an average (arithmetic mean) of only 20 microwaves per month. What was the average number of microwaves sold per month during the entire 22-month period ？（）

The enrollments at College X and College Y both grew by...

单项选择题The enrollments at College X and College Y both grew by 8 percent from 1980 to 1985. If the enrollment at College X grew by 800 and the enrollment at College Y grew by 840, the enrollment at College Y was how much greater than the enrollment at College X in 1985 ？（）