A-A+
Two hundred multiples of seven are chosen at r
问题详情
Two hundred multiples of seven are chosen at random, and 300 multiples of eight are chosen at random. Approximately what percentage of the 500 selected numbers are odd？
A．20%
B．25%
C．40%
D．5O%
E．80%
参考答案
正确答案：A
解析：All multiples of 8 are even, and half of the multiples of 7 are odd; the multiples of 7 make up 2/5 of the total, so if 1/2 of those multiples of 7 are odd, then 1/5 of the total will be odd, or 20%.
