What is the total amount on the fourth day...

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Please help me understand how to get to the answer. Thank you :)

A certain library assesses fines for overdue boos as follows. First day it is overdue, the total fine is $0.10. For each additional day, the total fine is either increased by $0.30 or doubled, whichever results in the lesser amount. What is the total amount on the fourth day it is overdue?

A. $0.60
B. $0.70
C. $0.80
D. $0.90
E. $1.00

The answer is B
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by GmatMathPro » Sat Dec 10, 2011 5:08 pm
gmatpup wrote:Please help me understand how to get to the answer. Thank you :)

A certain library assesses fines for overdue boos as follows. First day it is overdue, the total fine is $0.10. For each additional day, the total fine is either increased by $0.30 or doubled, whichever results in the lesser amount. What is the total amount on the fourth day it is overdue?

A. $0.60
B. $0.70
C. $0.80
D. $0.90
E. $1.00

The answer is B
The total fine on the....

first day=10

second day=20 (doubling makes the fine 20, adding 30 makes it 40, so we doubled)

third day=40 (doubling makes the fine 40, adding 30 makes it 50, so we doubled)

fourth day=70 (doubling makes the fine 80, adding 30 makes it 70, so we add 30)
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by gmatpup » Sat Dec 10, 2011 5:21 pm
OH WOW now I see!! I read the question as meaning that I had to either choose to double the total or add 30 ALL THROUGHOUT.. I didnt realize I could choose through each step.

Thank you so much :)