GWD 24 -Q16

[evelyn_yeh]

16
From May 1 to May 30 in the same year, the balance in a checking account increased. What was the balance in the checking account on May 30?
(1) If, during this period of time, the increase in the balance in the checking account had been 12 percent, then the balance in the account on May 30 would have been $504
(2) During this period of time, the increase in the balance in the checking account was 8 percent.

ANS(A)
怎麼可能是 A??
是 C 唄!!
WHY??

[evelyn_yeh]

有人願意為我解惑嗎???

[simonyu]

我也覺得是C耶，奇怪～

[王志元]

投C一票
May 1 =Bs
May 30=Be

(1) Be=1.12BS=504
=> Bs= 504/1.12
12%為(1)假設，實際未知 =>不充分
(2) Be=1.08Bs
Bs未知 =>不充分

(1) + (2)
Be= 1.08 (504/1.12) =>充分