关于economic growth

题目

关于economic growth
real GDP per person in the country of Flip is $10,000,and the growth rate is 10 percent a year,real gdp person in the country of Flap is $20,000and the growth rate is 5 percent a year.when will real gap per person be greater in Flip than in Flap

答案

Flip国GDP：起始10000刀,每年涨10%
Flap国GDP:起始20000刀,每年涨5%
求Flip过GDP哪一年能超过FLAP国?
10000*(1+10%)^x=20000*(1+5%)^x
^x这个代表的是括号里的x次方
解方程就好咯,最后得x=14.9年约等15年.
不明白再问