∑ ( from n = 1 to n =5 ) 3 · ( -2 ) ^( n -1 )
a 1 = 3 · ( -2 ) ^0 = 3
a 2 = 3 · ( - 2 ) = - 6
a 3 = 3 · 4 = 12
a 4 = 3 · ( - 8 ) = - 24
a 5 = 3 · 16 = 48
3 - 6 + 12 - 24 + 48 = 33
Answer: C ) 33
First calculate the hourly rate, which is the difference of cleaning 2 and 1 rooms:
175-125=50
then calculate the initial value by subtracting the hourly rate from the "1 room" cost:
125-50=75
The initial cost might be something like driving to the place (which is only necessary once), while the rate covers work time or cleaning utensils used.
Answer:
In order to find the fraction of the 20 dollars that has been spent, we have to divide the amount spent by the total amount. So 0.65 is the fraction of 20 that is spent.
Step-by-step explanation:
BA and BD are radii of the circle, so triangle ABD is isosceles. Then angles BDA and BAD are congruent, and the remaining (central) angle ABD has measure

Angles ABD and CBD are supplementary, so

and the answer is E.