推 dougho:2)是因為打8折之後再打85折 所以是原本的68折 11/28 15:45
~濤濤版31回
13-Q14:
$10,000 is deposited in a certain account that pays r percent annual interest
compounded annually, the amount D(t), in dollars, that the deposit will grow
to in t years is given by D(t) = 10,000 {1+(r/100)}^t.
What amount will the deposit grow to in 3 years?
(1) D(t) = 11,000
(2) r =10
Answer: D
題目(1)要改成D(1) = 11,000 才能算的出來嗎??
CD討論眾說紛紜@@~
30-Q15
At a certain bookstore, the regular price of each book is 20 percent less
than its list price. If during a sale the price of each book at the store
was 15 percent less than its regular price, then the price of a book during
the sale was what percent less than its list price?
A. 30%
B. 32%
C. 35%
D. 38%
E. 40%
----------------------------------------------------------------------------------------------------------------------
Answer: B
1-(1-20%)(1-15%)=1-0.68=0.32=32%
我看不懂解答的意思耶?? 為什麼(1-20%)要乘(1-15%)~不是比少多少嗎???
※ 編輯: chilis 來自: 59.104.60.241 (11/28 15:31)