Math problem 2

题目

Math problem 2
A clock takes 4 seconds to strike 5 o'clock. How long will it take to strike 10 o'clock? (Hint:The answer is not 8 seconds.)
2.John, Jack, Jim, and Joe all decided to take up horseback riding. Jim went twice as many times as jack, and john went four more times than joe but three less times than jim. Joe went 15 times altogether. How many times did jack go?

答案

第一题（不保证对）
5个小时=5*60分*60秒=18000
再加上最早差的4秒18000+4=18004秒
第二题
jack a jim b joe c john d
b=2a
d=c+4
d=b-3
c=15
求a
d=15+4=19=b-3 b=22 a=11