南外英语数学题Do you know the different between number and digit?

问题描述:

南外英语数学题Do you know the different between number and digit?
do you know the different between number and digit?Nancy has a book.Now she wants to number the pages with 813 digits.How many pages does the book have?
大家答的都很好,babybluein答得更详细些,所以最佳就给他啦,

number表示一个数,digit表示一个数字
如:18是一个number,有2个digits
而题目说Nancy有本书,每页的页码的数中的数字个数加起来是813,问这本书有多少页?
首先,1到9有9个数字.
接下来就是两位数,10-99有90*2=180个数字.
而书里有813个数字,所以还余下813-9-180=624个数字.
接下来编码的页码都是三位数,624可以编624/3=208个页码.
所以这本书有100+208-1=307页.