您好,两种都可以,主要是数学式子的变换:(F/P,9%,4)→F=P*(1+9%)^4→F/P=(1+9%)^4,(F/P,9%,5)→F=P*(1+9%)^5→F/P=(1+9%)^5,(F/A,9%,4)→F=A+A*(1+9%)+A(1+9%)^2+A(1+9%)^3→F/A={1+(1+9%)+(1+9%)^2+(1+9%)^3},所以(F/A,9%,5)→F=A+A*(1+9%)+A(1+9%)^2+A(1+9%)^3+A(1+9%)^4→F/A={1+(1+9%)+(1+9%)^2+(1+9%)^3+(1+9%)^4},(F/A,9%,,5)=(F/A,9%,4)+(F/P,9%,4)所以书上是对的,(F/A,9%,5)={1+(1+9%)+(1+9%)^2+(1+9%)^3}*(1+9%)+1=(F/A,9%,4)*(1+9%)+1所以题库解题思路也是对的。