Question

英语数学问题（翻译+解题）

An integer is called 'octal'.If it is divisible by 8 or if at least one of its digits is eight.How many integers between 0 and 100 are octal?

Answer 1

【解释】
一种整数被称为“octal”，它能被8整除或至少有一位数是8。在0至100中，有多少个整数是octal？
【解题】
divisible by 8( its digits is eight 4) :
8,16,24,32,40,48,56,64,72,80,88,96
at least one of its digits is eight(divisible by eight 4) :
18,28,38,(48),58,68,78,(88)[(80),81,82,83,84,85,86,87,89],89
∴ 12+19-4=27
The 'octal' integers between 0 and 100 are 27.

Answer 2

如果一个整数可以被8整除，或者有一个位数是8，那么1-100中有多少个这样的数？
8.16.24.32.40.48.56.64.72.80.88.96
18.28.38.58.68.78.98
81.82.83.84.85.86.87.89.共12+7+8=27个